1. Concealment of ovulation, parental care, and human social evolution;Alexander,1979
2. Human Sperm Competition;Baker,1995
3. The risk of conception on different days of the menstrual cycle;Barrett;Population Science,1969
4. Despotism and Differential Reproduction. A Darwinian view of History;Betzig,1986
5. Roman polygyny;Betzig;Ethology and Sociobiology.,1992