Perls, F. (1951). Gestalt therapy: Excitement and growth (ed.). Delta.
Lua i Stíl Chicago (17ú heag.)Perls, Frederick. Gestalt Therapy: Excitement and Growth. ed. New York: Delta, 1951.
Lua MLA (9ú heag.)Perls, Frederick. Gestalt Therapy: Excitement and Growth. ed. Delta, 1951.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.