O'Connor, N., & Hermelin, B. (1963). Speech and thought in severe subnormality; an experimental study. Macmillan.
Lua i Stíl Chicago (17ú heag.)O'Connor, N., agus Beate Hermelin. Speech and Thought in Severe Subnormality; an Experimental Study. New York: Macmillan, 1963.
Lua MLA (9ú heag.)O'Connor, N., agus Beate Hermelin. Speech and Thought in Severe Subnormality; an Experimental Study. Macmillan, 1963.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.