Bonobo Sex and Societyபரணிடப்பட்டது 2016-03-04 at the வந்தவழி இயந்திரம், by: de Waal, Frans B.M., Scientific American, 00368733, Mar95, Vol. 272, Issue 3 (Word document) "They also practice so-called penis-fencing, in which two males hang face to face from a branch while rubbing their erect penises together."
Bonobo Sex and Societyபரணிடப்பட்டது 2016-03-04 at the வந்தவழி இயந்திரம், by: de Waal, Frans B.M., Scientific American, 00368733, Mar95, Vol. 272, Issue 3 (Word document) "They also practice so-called penis-fencing, in which two males hang face to face from a branch while rubbing their erect penises together."
