Hawkins,Mike. (1997). Social Darwinism in European and American thought 1860-1945: Nature as model and nature as threat. Cambridge university press.
Lua i Stíl Chicago (17ú heag.)Hawkins,Mike. Social Darwinism in European and American Thought 1860-1945: Nature as Model and Nature as Threat. Cambridge, New York: Cambridge university press, 1997.
Lua MLA (9ú heag.)Hawkins,Mike. Social Darwinism in European and American Thought 1860-1945: Nature as Model and Nature as Threat. Cambridge university press, 1997.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.