(1981). The Evolving Biosphere General / Editor, Ph Greenwood; Editor, P L. Porey. Cambridge University Press.
Lua i Stíl Chicago (17ú heag.)The Evolving Biosphere General / Editor, Ph Greenwood; Editor, P L. Porey. Cambridge University Press, 1981.
Lua MLA (8ú heag.)The Evolving Biosphere General / Editor, Ph Greenwood; Editor, P L. Porey. Cambridge University Press, 1981.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.