APA

Simpson G. G., . (261933). A new fossil snake from the Notostylops Beds of Patagonia. New York: American Museum of Natural History.

Chicago

Simpson George Gaylord, . 261933. A new fossil snake from the Notostylops Beds of Patagonia. New York: American Museum of Natural History.

Harvard

Simpson G. G., . (261933). A new fossil snake from the Notostylops Beds of Patagonia. New York: American Museum of Natural History.

MLA

Simpson George Gaylord, . A new fossil snake from the Notostylops Beds of Patagonia. New York: American Museum of Natural History. 261933.