Goddard, H. H. (1912). The Kallikak family: A study in the heredity of feeblemindedness. The Macmillan Company.
Lua i Stíl Chicago (17ú heag.)Goddard, Henry Herbert. The Kallikak Family: A Study in the Heredity of Feeblemindedness. New York: The Macmillan Company, 1912.
Lua MLA (8ú heag.)Goddard, Henry Herbert. The Kallikak Family: A Study in the Heredity of Feeblemindedness. The Macmillan Company, 1912.
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