Some corrected citations:
For some years now I have been quoting things. There are 4 key articles. I have often made small errors, so if you are interested these are the best I can do with the key ones.
On the Regulation of Populations of Mammals, Birds, Fish, and Insects, Richard M. Sibly et al. SCIENCE vol. 309 no. 5734 July 22, 2005 page 607 – 610
An Association between Kinship and Fertility of Human Couples, Agnar Helgason et al. SCIENCE vol. 329 no. 5864 February 8, 2008 page 813 – 816
Human Fertility Increases with Marital Radius, Rodrigo Labouriau et al. GENETICS vol. 178 no. 1 January, 2008 page 601 – 603
Comment on “An Association between Kinship and Fertility of Human Couples,” Rodrigo Labouriau et al. SCIENCE vol. 322 no. 5908 December 12, 2008 page 1634 – 1635
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