Requested reference
Platnick, N. I. & Shadab, M. U. (1976a). A revision of the spider genera Drassodes and Tivodrassus (Araneae, Gnaphosidae) in North America. American Museum Novitates 2593: 1-29. 
-- Show included taxa
Platnick, N. I. & Shadab, M. U. (1976a). A revision of the spider genera Drassodes and Tivodrassus (Araneae, Gnaphosidae) in North America. American Museum Novitates 2593: 1-29. -- Show included taxa