Douglas, T. (1983). Groups: Understanding-- together. Tavistick.
Lua i Stíl Chicago (17ú heag.)Douglas, Tom. Groups: Understanding-- Together. London: Tavistick, 1983.
Lua MLA (9ú heag.)Douglas, Tom. Groups: Understanding-- Together. Tavistick, 1983.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.