Volpe, E. P. (1993). Biology and human concerns (4th ed.). Wm. C. Brown.
Lua i Stíl Chicago (17ú heag.)Volpe, E. Peter. Biology and Human Concerns. 4th ed. Dubuque: Wm. C. Brown, 1993.
Lua MLA (9ú heag.)Volpe, E. Peter. Biology and Human Concerns. 4th ed. Wm. C. Brown, 1993.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.