Newman, H. H., Freeman, F. N., & Holzinger, K. J. (1937). Twins: A study of heredity and environment. The University of Chicago Press.
Lua i Stíl Chicago (17ú heag.)Newman, Horatio Hackett, Frank N. Freeman, agus Karl J. Holzinger. Twins: A Study of Heredity and Environment. Chicago, Ill.: The University of Chicago Press, 1937.
Lua MLA (8ú heag.)Newman, Horatio Hackett, et al. Twins: A Study of Heredity and Environment. The University of Chicago Press, 1937.
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