Ramírez-Benavides, W.; Monge-Nájera, J.; B. Chavarría, J. Sex Ratio in Two Species of Pegoscapus Wasps (Hymenoptera: Agaonidae) That Develop in Figs: Can Wasps Do Mathematics, or Play Sex Ratio Games?. Rev. Biol. Trop. 2009, 57, 605−621.