1. Steven R. Asher, Sherri L. Olden und John M. Gottman, Children’s Friendships in School Settings, in: Lilian G. Katz (Hrsg.), Current Topics in Early Childhood Education, Bd. 1, Norwood, N.J. 1977, S. 33-61.
2. Allan P. Bates und Nicholas Babchuk, The Primary Group: A Reappraisal, in: Sociological Quarterly, 3, 1961, S. 181-191.
3. Frederick L. Bates und Clyde C. Harvey, The Structure of Social Systems, New York 1975.
4. Jere M. Cohen, Sources of Peer Group Homogenity, in: Sociology of Education, 50, 1977, S. 227-241.
5. James S. Coleman, The Adolescent Society, New York 1961.