Manson, J. H.; Perry, S.; Parish, A. R. (October 1997). "Nonconceptive sexual behavior in bonobos and capuchins". International Journal of Primatology. 18 (5): 767–786. doi:10.1023/A:1026395829818. S2CID3032455.
Manson, J. H.; Perry, S.; Parish, A. R. (October 1997). "Nonconceptive sexual behavior in bonobos and capuchins". International Journal of Primatology. 18 (5): 767–786. doi:10.1023/A:1026395829818. S2CID3032455.