Pepper, D. (1984). The roots of modern environmentalism. Routledge.
Chicago-čujuhus (17. p.)Pepper, David. The Roots of Modern Environmentalism. London: Routledge, 1984.
MLA-čujuhus (9. p.)Pepper, David. The Roots of Modern Environmentalism. Routledge, 1984.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.