Johnson, F. P., & Johnson, D. W. (1994). Joining together: Group theory and group skills (5th ed.). Allyn and Bacon.
Cita Chicago (17th ed.)Johnson, Frank P., i David W. Johnson. Joining Together: Group Theory and Group Skills. 5th ed. Boston: Allyn and Bacon, 1994.
Cita MLA (9th ed.)Johnson, Frank P., i David W. Johnson. Joining Together: Group Theory and Group Skills. 5th ed. Allyn and Bacon, 1994.
Atenció: Aquestes cites poden no estar 100% correctes.