Cita APA (7th ed.)
Johnson, D. W., & Johnson, F. P. (1991). Joining together: Group theory and group skills (4th ed.). Prentice-Hall.
Cita Chicago (17th ed.)
Johnson, David W., i Frank P. Johnson. Joining Together: Group Theory and Group Skills. 4th ed. Englewood Cliffs, N.J.: Prentice-Hall, 1991.
Cita MLA (9th ed.)
Johnson, David W., i Frank P. Johnson. Joining Together: Group Theory and Group Skills. 4th ed. Prentice-Hall, 1991.
Atenció: Aquestes cites poden no estar 100% correctes.