Penrose, L. S. (1963). The biology of mental defect ([2nd rev. ed.].). Grune & Stratton.
Chicago Style aipamenaPenrose, Lionel Sharples. The Biology of Mental Defect. [2nd rev. ed.]. New York: Grune & Stratton, 1963.
MLA aipamenaPenrose, Lionel Sharples. The Biology of Mental Defect. [2nd rev. ed.]. Grune & Stratton, 1963.
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