Não informado. (1964). MENTAL RETARDATION ABSTRACTS. National Clearinghouse for Mental Health Information.
Chicago-referens (17:e uppl.)Não informado. MENTAL RETARDATION ABSTRACTS. Bethesda, Md: National Clearinghouse for Mental Health Information, 1964.
MLA-referens (8:e uppl.)Não informado. MENTAL RETARDATION ABSTRACTS. National Clearinghouse for Mental Health Information, 1964.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.