Ewart, R. J. (1915). The Influence of Age of the Grandparent at the Birth of the Parent on the Number of Children born and their Sex.
Chicago-tyylinen lähdeviittausEwart, R. J. The Influence of Age of the Grandparent At the Birth of the Parent On the Number of Children Born and Their Sex. 1915.
MLA-viiteEwart, R. J. The Influence of Age of the Grandparent At the Birth of the Parent On the Number of Children Born and Their Sex. 1915.
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