Symbolic interactionism

Symbolic interactionism is a sociological perspective which developed around the middle of the twentieth century and that continues to be influential in some areas of the discipline. It is particularly important in microsociology and social psychology. Symbolic interactionism is derived from the American philosophy of pragmatism and particularly from the work of George Herbert Mead.

Herbert Blumer, a student and interpreter of Mead, coined the term "symbolic interactionism" and put forward an influential summary of the perspective: people act toward things based on the meaning those things have for them, and these meanings are derived from social interaction and modified through interpretation.[1]

Sociologists working in this tradition have researched a wide range of topics using a variety of research methods. However, the majority of interactionist research uses qualitative research techniques, like participant observation, to study aspects of (1) social interaction and/or (2) individuals' selves.

History

Symbolic interaction was invented by George Herbert Mead and Charles Horton Cooley. Mead argued that people's selves are social products, but that these selves are also purposive and creative, and believed that the true test of any theory was that it was "useful in solving complex social problems" (Griffin 59). Mead's influence on symbolic interactionism was said to be so powerful that other sociologists regard him as the one "true founder" of the symbolic interactionism tradition. Although Mead taught in a philosophy department, he is best known by sociologists as the teacher who trained a generation of the best minds in their field. Strangely, he never set forth his wide-ranging ideas in a book or systematic treatise. After his death in 1931, his students pulled together class notes and conversations with their mentor and published Mind, Self and Society in his name. (Griffin 59). 'It is a common misconception that John Dewey was the leader of this sociological theory; however, according to The Handbook of Symbolic Interactionism, Mead was undoubtedly the individual who "transformed the inner structure of the theory, moving it to a higher level of theoretical complexity" (Herman-Kinney Reynolds 67).[2]

Herbert Blumer was a social constructionist, and was influenced by Dewey; as such, this theory is very phenomenologically based. He believed that the "Most human and humanizing activity that people engage in is talking to each other" (Griffin 60).[3] Two other theorists who have influenced Symbolic interaction theory are Yrjö Engeström and David Middleton. Engeström and Middleton explained the usefulness of symbolic interactionism in the communication field in a variety of work settings, including "courts of law, health care, computer software design, scientific laboratory, telephone sales, control, repair, and maintenance of advance manufacturing systems."[4] Other scholars credited for their contribution to the theory are Thomas, Park, James, Horton, Cooley, Znaniecki, Baldwin, Redfield, and Wirth.[5]

Basic premises and approach

The term "symbolic interactionism" has come into use as a label for a relatively distinctive approach to the study of human life and human conduct (Blumer, 1969). With symbolic interactionism, reality is seen as social, developed interaction with others. Most symbolic interactionists believe a physical reality does indeed exist by an individual's social definitions, and that social definitions do develop in part or relation to something "real". People thus do not respond to this reality directly, but rather to the social understanding of reality; i.e., they respond to this reality indirectly through a kind of filter which consists of individuals' different perspectives. This means that humans exist not in the physical space composed of realities, but in the "world" composed only of "objects". According to Blumer, the "objects" can be divided into three types: physical objects, social objects, and abstract objects.

Both individuals and society cannot be separated far from each other for two reasons. One, being that they are both created through social interaction, and two, one cannot be understood in terms without the other. Behavior is not defined by forces from the environment or inner forces such as drives, or instincts, but rather by a reflective, socially understood meaning of both the internal and external incentives that are currently presented (Meltzer et al., 1975).[6]

Herbert Blumer (1969) set out three basic premises of the perspective:

The first premise includes everything that a human being may note in their world, including physical objects, actions and concepts. Essentially, individuals behave towards objects and others based on the personal meanings that the individual has already given these items. The second premise explains the meaning of such things is derived from, or arises out of, the social interaction that one has with other humans. Blumer, following Mead, claimed people interact with each other by interpreting or defining each other's actions instead of merely reacting to each other's actions. Their "response" is not made directly to the actions of one another but instead is based on the meaning which they attach to such actions. Thus, human interaction is mediated by the use of symbols and signification, by interpretation, or by ascertaining the meaning of one another's actions (Blumer 1962). Meaning is either taken for granted and pushed aside as an unimportant element which need not to be investigated or it is regarded as a mere neutral link or one of the causal chains between the causes or factors responsible for human behavior and this behavior as the product of such factors. (Blumer 1969). Social interaction is the source of meaning, and out of which the typical communication media which have meanings, i.e., the language arises, and is negotiated through the use of it. We have the ability to name things and designate objects or actions to a certain idea or phenomenon. The use of symbols is a popular procedure for interpretation and intelligent expression. Blumer contrasted this process with behaviorist explanations of human behavior, which does not allow for interpretation between stimulus and response.

In Blumer's third premise the idea of minding comes into play. Symbolic interactionists describe thinking as an inner conversation. (Griffin 62). Mead called this inner dialogue minding. Minding is the delay in one's thought process that happens when one thinks about what they will do next. The third premise is that these meanings are handled in, and modified through, an interpretative process[7] used by the person in dealing with the things he encounters. We naturally talk to ourselves in order to sort out the meaning of a difficult situation. But first, we need language. Before we can think, we must be able to interact symbolically. (Griffin 62). The emphasis on symbols, negotiated meaning, and social construction of society brought on attention to the roles people play. Role-taking is a key mechanism that permits people to see another person's perspective to understand what an action might mean to another person. Role-taking is a part of our lives at an early age. Playing house and pretending to be someone else are examples of this phenomena. There is an improvisational quality of roles; however, actors often take on a script that they follow. Because of the uncertainty of roles in social contexts, the burden of role-making is on the person in the situation. In this sense, we are proactive participants in our environment.[8]

Mind, Self and Society

Mind, Self and Society is the book published by Mead's students based on his lectures and teaching. The title of the book serves as the key concepts of symbolic interaction theory. The mind refers to an individual's ability to use symbols to create meanings for the world around him. Individuals use language and thought to accomplish this goal. Self refers to an individual's ability to reflect on the way that he/she is perceived by others. Finally, society, according to Mead is where all of these interactions are taking place.

The "I" and the "me"

While establishing the idea of self, Mead introduces a distinction between the "I" and the "me", respectively, the active and socialized aspects of the person. The "me" is a similar concept to Cooley's looking-glass self. An example of these concepts is the pygmalion effect whereby a person (I) behaves to match the sense of self (me) they derive from others, in a form of self-fulfilling prophecy.

Research and methods

Sociologists working in this tradition have researched a wide range of topics using a variety of research methods. However, the majority of interactionist research uses qualitative research methods, like participant observation, to study aspects of 1) social interaction, and/or 2) individuals' selves. Participant observation allows researchers to access symbols and meanings, as in Howard S. Becker's Art Worlds (1982) and Arlie Hochschild's The Managed Heart (1983).[9] They argue that close contact and immersion in the everyday activities of the participants is necessary for understanding the meaning of actions, defining situations and the process that actors construct the situation through their interaction. Because of this close contact, interactions cannot remain completely liberated of value commitments. In most cases, they make use of their values in choosing what to study; however, they seek to be objective in how they conduct the research. Therefore, the symbolic-interaction approach is a micro-level orientation focusing in close up human interaction in specific situations.

Sociological subfields that have been particularly influenced by symbolic interactionism include the sociology of emotions, deviance/criminology, collective behavior/social movements, and the sociology of sex. Interactionist concepts that have gained widespread usage include definition of the situation, emotion work, impression management, looking glass self, and total institution. Semiology is connected to this discipline, but unlike those elements of semiology which are about the structures of language, interactionists typically are more interested in the ways in which meaning is fluid and ambiguous.[9]

Ethnomethodology, an offshoot of symbolic interactionism, questions how people's interactions can create the illusion of a shared social order despite not understanding each other fully and having differing perspectives. Harold Garfinkel demonstrated this by having his students perform "experiments in trust", called breaching experiments, where they would interrupt ordinary conversations because they refused to take for granted that they knew what the other person was saying. They would demand explanations and then explanations of the explanations (Garfinkel 1967) to gain understanding of each other's definitions and perspectives. Further and more recent ethnomethodologist research has performed detailed analyses of basic conversations to reveal the methods of how turn-taking and alternative conversational maneuvers are managed.[8]

Five central ideas behind symbolic interactionism

There are five central ideas to symbolic interactionism according to Joel M. Charon, author of Symbolic Interactionism An Introduction, An Interpretation, An Integration:

  1. "The human being must be understood as a social person. It is the constant search for social interaction that leads us to do what we do. Instead of focusing on the individual and his or her personality, or on how the society or social situation causes human behavior, symbolic interactionism focuses on the activities that take place between actors. Interaction is the basic unit of study. Individuals are created through interaction; society too is created through social interaction. What we do depends on interaction with others earlier in our lifetimes, and it depends on our interaction right now. Social interaction is central to what we do. If we want to understand cause, focus on social interaction.
  2. The human being must be understood as a thinking being. Human action is not only interaction among individuals but also interaction within the individual. It is not our ideas or attitudes or values that are as important as the constant active ongoing process of thinking. We are not simply conditioned, we are not simply beings who are influenced by those around us, we are not simply products of society. We are, to our very core, thinking animals, always conversing with ourselves as we interact with others. If we want to understand cause, focus on human thinking.
  3. Humans do not sense their environment directly, instead, humans define the situation they are in. An environment may actually exist, but it is our definition of it that is important. Definition does not simply randomly happen; instead, it results from ongoing social interaction and thinking.
  4. The cause of human action is the result of what is occurring in our present situation. Cause unfolds in the present social interaction, present thinking, and present definition. It is not society’s encounters with us in our past, that causes action nor is it our own past experience that does. It is, instead, social interaction, thinking, definition of the situation that takes place in the present. Our past enters into our actions primarily because we think about it and apply it to the definition of the present situation.
  5. Human beings are described as active beings in relation to their environment. Words such as conditioning, responding, controlled, imprisoned, and formed are not used to describe the human being in symbolic interaction. In contrast to other social-scientific perspectives humans are not thought of as being passive in relation to their surroundings, but actively involved in what they do."[10]

Central interactionist themes

To Herbert Blumer’s conceptual perspective, he put them in three core principles: that people act toward things, including each other, on the basis of the meanings they have for them; that these meanings are derived through social interaction with others; and that these meanings are managed and transformed through an interpretive process that people use to make sense of and handle the objects that constitute their social worlds. Keeping in mind of Blumer’s earlier work, David A. Snow, professor of Sociology at the University of California, suggests four broader and even more basic orienting principles: human agency, interactive determination, symbolization, and emergence. Snow uses these four principles as the thematic bases for identifying and discussing contributions to the study of social movements.

Human agency

Human agency emphasizes the active, willful, goal seeking character of human actors. The emphasis on agency focuses attention on those actions, events, and moments in social life in which agentic action is especially palpable.

Interactive determination

Interactive determination specifies that understanding of focal objects of analysis, whether they are self-concepts, identities, roles, practices, or even social movements. Basically this means, neither individual, society, self, or others exist only in relation to each other and therefore can be fully understood only in terms of their interaction.

Symbolization

Symbolization highlights the processes through which events and conditions, artifacts, people, and other environmental features that take on particular meanings, becoming nearly only objects of orientation. Human behavior is partly contingent on what the object of orientation symbolizes or means.

Emergence

Emergence focuses on attention on the processual and nonhabituated side of social life, focusing not only on organization and texture of social life, but also associated meaning and feelings. The principal of emergence tells us not only to possibility of new forms of social life and system meaning but also to transformations in existing forms of social organization. (Herman-Kinney Reynolds 812-824).[2]

New media

New Media is a term used to define all that is related to the internet and the interplay between technology, images and sound.[11] As studies of online community proliferate, the concept of online community has become a more accepted social construct. Studies encompassed discursive communities;[12][13] identity;[14][15] community as social reality;[16] networking;[17] the public sphere;[18] ease and anonymity in interactions.[19] These studies show that online community is an important social construct in terms of its cultural, structural, political and economic character.

It has been demonstrated that people's ideas about community are formed, in part, through interactions both in online forums as well as those in face to face interactions. As a result, people act in their communities according to the meanings they derive about their environment, whether online or offline, from those interactions. This perspective reveals that online communication may very well take on different meanings for different people depending on information, circumstance, relationships, power, and other systems that make up communities of practice. People enact community the way it is conceived and the meaning of community evolves as they come up with new ways to utilize it. Given this reality, scholars are continually challenged to research and understand how online communities are comprised, how they function, and how they are connected to offline social life.[20]

Symbolic interaction theory was discussed in “The Cyberself: The Self-ing Project goes online, Symbolic Interaction in the Digital Age.” Robinson discusses how symbolic interaction theory explains the way individuals create a sense of self through their interactions with others. However, she believes advances in technology have changed this. The article investigates the manner in which individuals form their online identity. She uses symbolic interaction theory to examine the formation of the cyber “I” and a digital “generalized other.” In the article, Robinson suggests individuals form new identities on the internet. She argues these cyber identities are not necessarily the way the individual would be perceived offline.[21]

Criticisms

Symbolic interactionists are often criticized for being overly impressionistic in their research methods and somewhat unsystematic in their theories. It is argued that the theory is not one theory, but rather, the framework for many different theories. Additionally, some theorists have a problem with symbolic interaction theory due to its lack of testability. These objections, combined with the fairly narrow focus of interactionist research on small-group interactions and other social psychological issues, have relegated the interactionist camp to a minority position among sociologists (albeit a fairly substantial minority). Much of this criticism arose during the 1970s in the U.S. when quantitative approaches to sociology were dominant. Perhaps the best known of these is by Alvin Gouldner.[22]

Framework and theories

Some critiques of symbolic interactionism are based on the assumption that it is a theory, and the critiques apply the criteria for a "good" theory to something that does not claim to be a theory. Some critics find the symbolic interactionist framework too broad and general when they are seeking specific theories. Symbolic interactionism is a theoretical framework rather than a theory (see Stryker and Vryan, 2003, for a clear distinction between the two as it pertains to symbolic interactionism).[23] Thus, specific theories, hypotheses, and conceptualizations must be (and have successfully been) derived from the general framework that symbolic interactionism provides before interactionist theories can be assessed on the basis of the criteria a good theory (e.g., containing falsifiable hypotheses), or interactionist-inspired conceptualizations can be assessed on the basis of effective conceptualizations. The theoretical framework, as with any theoretical framework, is vague when it comes to analyzing empirical data or predicting outcomes in social life. As a framework rather than a theory, many scholars find it difficult to use. Interactionism being a framework rather than a theory makes it impossible to test interactionism in the manner that a specific theoretical claim about the relationship between specific variables in a given context allows. Unlike the symbolic interactionist framework, the many theories derived from symbolic interactionism, such as role theory and the versions of Identity Theory developed by Stryker,[24][25] and Burke and colleagues,[26][27] clearly define concepts and the relationships between them in a given context, thus allowing for the opportunity to develop and test hypotheses. Further, especially among Blumerian processual interactionists, a great number of very useful conceptualizations have been developed and applied in a very wide range of social contexts, types of populations, types of behaviors, and cultures and subcultures.

Social structure

Symbolic interactionism is often related and connected with social structure. This concept suggests that symbolic interactionism is a construction of people’s social reality.[24] It also implies that from a realistic point of view, the interpretations that are being made will not make much difference. When the reality of a situation is defined, the situation becomes a meaningful reality. There are many aspects and factors that go into this theory. This includes methodological criticisms, and critical sociological issues. A number of symbolic interactionists have addressed these topics, the best known being Sheldon Stryker's structural symbolic interactionism[24][28] and the formulations of interactionism heavily influenced by this approach (sometimes referred to as the "Indiana School" of symbolic interactionism), including the works of key scholars in sociology and psychology using different methods and theories applying a structural version of interactionism that are represented in a 2003 collection edited by Burke et al.[29] Another well-known structural variation of symbolic interactionism that applies quantitative methods is Manford H. Kuhn's (Kuhn and McPartland, 1954) formulation which is often referred to in sociological literature as the "Iowa School." Negotiated Order Theory" also applies a structural approach.[30]

According to this theory, language is the source of all meaning.[8] Social constructionist Herbert Blumer illuminates several key features about Social Interactionism. Most people interpret things based on assignment and purpose. The interaction occurs once the meaning of something has become identified. This concept of meaning is what starts to construct the framework of social reality. By aligning social reality, Blumer suggests that language is the meaning of interaction. Communication, especially in the form of symbolic interactionism is connected with language. Language initiates all forms of communication, verbal and non-verbal. Blumer defines this source of meaning as a connection that arises out of the social interaction that people have with each other.

There are many ways that Social Interactionism is connected with critical perspective. This relates to the overall social structure because they both have similar points of convergence and synergism. According to social theorist Patricia Burbank, these concepts of synergistic and diverging properties are what shape the viewpoints of humans as social beings. These two concepts are different in a sense because of their views of human freedom and their level of focus.

According to Burbank, actions are based on the effects of situations that occur during the process of Social Interaction. Another important factor in meaningful situations is the environment in which the social interaction occurs. The environment influences interaction, which leads to a reference group, which connects with perspective, and then concludes to a definition of the situation. This illustrates the proper steps to define a situation. An approval of the action occurs once the situation is defined. An interpretation is then made upon that action, which may ultimately influence the perspective, action, and definition.

Sheldon Stryker, a social constructionist has had an incredible amount of influence on the field of Social Interactionism. Stryker emphasizes that the sociology world at large is the most viable and vibrant intellectual framework because of the concept of the wider community people live in is made possible because of communication, which fuels symbolic interactionism.[24] Symbolic interactionism revitalizes society by illuminating our thoughts, actions and gestures as well. By being made up of our thoughts self-belief, the Social Interactionism Theory is the purpose of all human interaction, and is what causes society to exist. This fuels criticisms of the symbolic interactionist framework for failing to account for social structure, as well as criticisms that interactionist theories cannot be assessed via quantitative methods, and cannot be falsifiable or tested empirically. Framework is important for the symbolic interaction theory because for in order for the social structure to form, there are certain bonds of communication that need to be established to create the interaction The published literature indicates that structural and processual variations of interactionism are both alive and well in sociology, as is the Blumerian tradition of interactionism, and interactionism has been used more explicitly and more frequently in psychology and anthropology as well. Much of the symbolic interactionist framework's basic tenets can be found in a very wide range of sociological and psychological work, without being explicitly cited as interactionist, making the influence of symbolic interactionism difficult to recognize given this general acceptance of its assumptions as "common knowledge." Many scholars do not know they are applying interactionist ideas in their own theoretical assumptions and formulations.[23]

Society for the Study of Symbolic Interaction

The Society for the Study of Symbolic Interaction (SSSI) is an international professional organization for scholars, who are interested in the study of Symbolic Interaction. SSSI holds a conference in conjunction with the meeting of the American Sociological Association and the Society for the Study of Social Problems. This conference typically occurs in August and sponsors the Society for the Study of Symbolic Interaction holds the Couch-Stone Symposium each spring. The society provides travel scholarships for student members interested in attending the annual conference.[31] At the annual conference, the Society for the Study of Symbolic Interaction sponsors yearly awards in different categories of symbolic interaction. Additionally, some of the awards are open to student members of the society. The Ellis-Bochner Autoethnography and Personal Narrative Research Award is given annually by the Society for the Study of Symbolic Interaction affiliate of the National Communication Association for the best article, essay, or book chapter in autoethnography and personal narrative research. The award is named after renowned autoethnographers Carolyn Ellis and Art Bochner. The society also sponsors a quarterly journal, Symbolic Interaction.[32] The organization also releases a newsletter, SSSI Notes.[33]

See also

References

  1. ↑ https://sites.google.com/site/sssinteraction/
  2. 1 2 Herman-Kinney Nancy J., Reynolds, Larry T. (2003). Handbook of Symbolic Interactionism. New York: AltaMira.
  3. ↑ Griffin, Emory A. (2006). A First Look at Communication Theory. Boston: McGraw-Hill.
  4. ↑ Engestrom, Yrjo, and David Middleton. "Cognition and Communication at Work."
  5. ↑ Blumer, H. (1969) Symbolic Interactionism; Perspective and Method. Englewood Cliffs, NJ: Prentice-Hall
  6. ↑ Meltzer B.N., Petras J.W. & Reynolds L.T.(1975). Symbolic Interactionism: Genesis, Varieties, and Criticism. Boston: Routledge and Kegan Paul.
  7. ↑ This process occurs in the form of interaction with oneself or taking into account of taking into account. See the following paper: Kuwabara T., and K. Yamaguchi, 2013, An Introduction to the Sociological Perspective of Symbolic Interactionism, The Joint Journal of the National Universities in Kyushu, Education and Humanities, 1(1), pp. 1-11.
  8. 1 2 3 Garfinkel, Harold. 1967. Studies in Ethnomethodology. Englewood Cliffs, NJ: Prentice-Hall.
  9. 1 2 Marshall, G. (1998). "symbolic interactionism". A Dictionary of Sociology. Encyclopedia.com. Retrieved on: 2011-09-20.
  10. ↑ Charon, Joel M. (2004). Symbolic Interactionism An Introduction, An Interpretation, An Integration. Boston: Pearson. p. 31. ISBN 978-0-13-605193-0.
  11. ↑ http://www.newmedia.org/what-is-new-media.html
  12. ↑ Reid, E.M. (1991) Electropolis: Communication and Community on internet Relay Chat’, Honours thesis, University of Melbourne.
  13. ↑ Howard,T. (1997) A Rhetoric of Electronic Communities. Greenwich, CT:Ablex.
  14. ↑ Bromberg, H. (1996) ‘Are MUDs Communities? Identity, Belonging and Consciousness in Virtual Worlds’, in R. Shields (ed.) Cultures of internet:Virtual Spaces, Real Histories, Living Bodies, pp. 143–52. London: Sage.
  15. ↑ Donath, J. (1999) ‘Identity and Deception in the Virtual Community’, in M.A. Smith and P. Kollock (eds) Communities in Cyberspace, pp. 29–59. New York: Routledge.
  16. ↑ Watson, N. (1997) ‘Why We Argue About Virtual Community: A Case Study of the phish.net Fan Community’, in S.G. Jones (ed.) Virtual Culture: Identity and Communication in Cybersociety, pp. 102–32.Thousand Oaks, CA: Sage.
  17. ↑ Wellman, B. (1997) ‘An Electronic Group is Virtually a Social Network’, in S. Kiesler (ed.) Culture of the internet, pp. 179–205. Mahwah, NJ: Lawrence Erlbaum Associates.
  18. ↑ Ess, C. (1996) ‘The Political Computer: Democracy, CMC, and Habermas’, in C. Ess (ed.) Philosophical Perspectives on Computer-Mediated Communication, pp. 197–230. Albany, NY: State University of New York.
  19. ↑ Anthropologist Wows Personal Democracy Forum. Whatever. Shelley Dubois. Wired Magazine. 30 June 2009.
  20. ↑ Fernback, J. Beyond the diluted community concept: a symbolic interactionist perspective on online social relations New Media & Society, February 2007 9: 49-69
  21. ↑ Robinson, L. The Cyberself: The Self-ing Project goes online, Symbolic Interaction in the Digital Age. 2007
  22. ↑ Harris, D. "Reading Guide to the Bits on Interactionism in: Gouldner A (1971) The Coming Crisis of Western Sociology, London: Heinemann Educational Books". Retrieved 2011-09-20.
  23. 1 2 Stryker, Sheldon, and Kevin D. Vryan. 2003. "The Symbolic Interactionist Frame." 3-28 in Handbook of Social Psychology, edited by John Delamater. New York: Kluwer Academic/Plenum Publishers.
  24. 1 2 3 4 Stryker, Sheldon. (1968). "Identity Salience and Role Performance: The Relevance of Symbolic Interaction Theory for Family Research." Journal of Marriage and the Family 30:558-564.
  25. ↑ Stryker, Sheldon. (1994). "Identity Theory: Its Development, Research Base, and Prospects." Studies in Symbolic Interaction 16:9-20.
  26. ↑ Burke, Peter J. (1980). "The Self: Measurement Requirements from an Interactionist Perspective." Social Psychology Quarterly 43:18-29.
  27. ↑ Burke, Peter J., and Donald C. Reitzes. (1981). "The Link between Identity and Role Performance." Social Psychology Quarterly 44:83-92.
  28. ↑ Stryker, Sheldon. 1980. Symbolic Interactionism: A Social Structural Version. Menlo Park, CA: Benjamin/Cummings.
  29. ↑ Peter Burke and Jan Stets Burke, Peter J., Timothy J. Owens, Richard T. Serpe, and Peggy A. Thoits (Eds.). (2003). Advances in Identity Theory and Research. New York: Kluwer Academic/Plenum.
  30. ↑ The Sociological Quarterly Volume 18, Issue 1, pages 126–142, January 1977
  31. ↑ "Society for the Study of Symbolic Interaction". Archived from the original on June 7, 2007.
  32. ↑
  33. ↑ "Welcome to SSSI". Society for the Study of Symbolic Interaction.

Sources

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