Fenchel, T. (1987). Ecology-potentials and limitations. Ecology Institute.
Lua i Stíl Chicago (17ú heag.)Fenchel, Tom. Ecology-potentials and Limitations. Berlín: Ecology Institute, 1987.
Lua MLA (9ú heag.)Fenchel, Tom. Ecology-potentials and Limitations. Ecology Institute, 1987.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.