Olson, E. C. (1962). Late Permian terrestrial vertebrates, U.S.A. and U.S.S.R. American Philosophical Society.
Lua i Stíl Chicago (17ú heag.)Olson, Everett Claire. Late Permian Terrestrial Vertebrates, U.S.A. and U.S.S.R. Philadelphia: American Philosophical Society, 1962.
Lua MLA (9ú heag.)Olson, Everett Claire. Late Permian Terrestrial Vertebrates, U.S.A. and U.S.S.R. American Philosophical Society, 1962.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.