Johnson, D. W., & Johnson, F. P. (1982). Joining together: Group theory and group skills (2nd.ed.). Prentice-Hall.
Lua i Stíl Chicago (17ú heag.)Johnson, David W., agus Frank P. Johnson. Joining Together: Group Theory and Group Skills. 2nd.ed. New Jersey: Prentice-Hall, 1982.
Lua MLA (9ú heag.)Johnson, David W., agus Frank P. Johnson. Joining Together: Group Theory and Group Skills. 2nd.ed. Prentice-Hall, 1982.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.