1. Primate Anatomy. An Introduction;Ankel-Simons,2000
2. Guenon birth seasons and correlatives with rainfall and food;Butynski,1990
3. Bonobo. The Forgotten Ape;De Waal,1997
4. Primate Sexuality;Dixson,1998
5. Vergleichende Untersuchungen Über das Sexual und Sozialverhalten der Krallenaffen (Hapalidae);Epple;Folia Primatol.,1967