1. Allport, G., & Postman, LJ. (1947). The psychology of rumor. New York: Holt.
2. Aran, G. (1975). Parachuting. American Journal of Sociology, 80, 124–152.
3. Becker, H.S. (1960). Notes on the concept of commitment. American Journal of Sociology, 66, 32–40.
4. Becker, H.S., Geer, B., Hughes, E., & Strauss, A. (1961). Boys in white: Student culture in medical school. Chicago: University of Chicago Press.
5. Blau, P. (1956). Social mobility and interpersonal relations. American Sociological Review, 21, 290–295.