APA

Howden H. F., Cartwrigth O. L., .Scarab beetles of the genus Onthophagus latreille North of Mexico (Coleoptera: Scarabaeidae). : .

Chicago

Howden Henry F, Cartwrigth Oscar L, .Scarab beetles of the genus Onthophagus latreille North of Mexico (Coleoptera: Scarabaeidae). : .

Harvard

Howden H. F., Cartwrigth O. L., .Scarab beetles of the genus Onthophagus latreille North of Mexico (Coleoptera: Scarabaeidae). : .

MLA

Howden Henry F, Cartwrigth Oscar L, .: . .