The five great apes (Gorilla, Common Chimpanzee, Bonobo, Orangutan, Human) have remarkably different mating systems.   The following readings provide an introduction.   Also read some hints and suggestions!

Mitani, J. C. 1990. Experimental field studies of Asian ape social systems.   International Journal of Primatology 11: 103-126. [this review is also relevant to African apes!]

Wrangham, R. W. 1993. The evolution of sociality in chimpanzees and bonobos.   Human Nature 4: 47-79. [an early review]

Parish, A. R. 1993. Sex and food control in the "uncommon chimpanzee": How bonobo females overcome a phylogenetic legacy of male dominance.   Ethology and Sociobiology 15: 157-179.

Morin, P. A., J. J. Moore, R. Chakraorty, L. Jin, J. Goodall, and D. S. Woodruff. 1994. Kin selection, social structure, gene flow, and the evolution of chimpanzees.   Science 265: 1193-1201.

Kano, T. 1996. Male ranking order and copulation rate in a unit-group of bonobos at Wamba, Zaire. In Great Ape Societies (W. C. McGrew, L. Marchant, and T. Nishida, editors), pp. 135-145. Cambridge University Press. [a chapter in an important book about great ape social behavior]

Parish, A. R. 1996. Female relationships in bonobos (Pan paniscus): evidence for bonding, cooperation, and female dominance in a male-philopatric species.   Human Nature 7: 61-96.

Gerloff, U., B. Hartung, B. Fruth, G. Hohmann, and D. Tautz. 1999. Intracommunity relationships, dispersal pattern and paternity success in a wild living community of bonobos (Pan paniscus) determined from DNA analysis of faecal samples.   Proceedings of the Royal Society, Biological Sciences, 266: 1189-1195.

Hohmann, G., and B. Fruth. 2003. Intra- and inter-sexual aggression by bonobos in the context of mating.   Behaviour 140: 1389-1413.

Harcourt, A. H., and K. J. Stewart. 2007. Male mating strategies and gorilla society.   In A. H. Harcourt and K. J. Stewart, Gorilla societies. Chapter 11 (pp. 267-302). University of Chicago Press.

Mitani, J. C. 1985. Sexual selection and adult male orangutan (Pongo pygmaeus) long calls.   Animal Behaviour 33: 272-283.

Mitani, J. C. 1985. Mating behaviour of male orangutans in the Kutai Game Reserve.   Animal Behaviour 33: 392-402.

Miller, L. C., A. Putcha-Bhagaavatula, and W. C. Pedersen. 2002. Men's and women's mating preferences: distinct evolutionary mechanisms?   Current Directions in Psychological Science 11: 88-93. [one of many papers on the subject!]