Pianka, E. R. (2000). Evolutionary ecology 6th ed (6th ed.). Benjamin/Cummings.
Lua i Stíl Chicago (17ú heag.)Pianka, Eric R. Evolutionary Ecology 6th Ed. 6th ed. San Francisco, CA: Benjamin/Cummings, 2000.
Lua MLA (9ú heag.)Pianka, Eric R. Evolutionary Ecology 6th Ed. 6th ed. Benjamin/Cummings, 2000.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.