G.  Halffter and Matthews, E. G., ?The natural history of dung beetles of the subfamily Scarabaeinae (Coleoptera: Scarabaeidae)?, Folia Entomologica Mexicana, vol. 12-14, pp. 1-312, 1966.

E. G.  Matthews, ?The taxonomy, geographic distribution and feeding habitas of the Canthonines of Puerto Rico (Coleoptera: Scarabaeidae)?, Transactions of the American Entomological Society, vol. 91, pp. 431-465, 1965.

E. G.  Matthews, ?A taxanomic and zoogeographic survey of the Scarabaeinae of the Antilles (Coleoptera: Scarabaeidae)?, Memoirs of the American Entomological Society, vol. 21, pp. 1-134, 1966.

E. G.  Matthews, ?La biogeografía ecológia de los escarabajos del estiércol?, Acta Politécnica Mexicana, vol. 16, pp. 89-98, 1975.

E. G.  Matthews and Halffter, G., ?The natural history of dung beetles of the subfamily Scarabaeinae (Coleoptera, Scarabaeidae)?, Folia Entomologica Mexicana, vol. 12-14, pp. 1-312, 1966.