Não informado. (1964). MENTAL RETARDATION ABSTRACTS. National Clearinghouse for Mental Health Information.
Chicago-viite (17. p.)Não informado. MENTAL RETARDATION ABSTRACTS. Bethesda, Md: National Clearinghouse for Mental Health Information, 1964.
MLA-viite (8. p.)Não informado. MENTAL RETARDATION ABSTRACTS. National Clearinghouse for Mental Health Information, 1964.
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