Coppens, C. (1909). A brief history of philosophy. Schwartz, Kirwin & Fauss.
Lua i Stíl Chicago (17ú heag.)Coppens, Charles. A Brief History of Philosophy. New York: Schwartz, Kirwin & Fauss, 1909.
Lua MLA (8ú heag.)Coppens, Charles. A Brief History of Philosophy. Schwartz, Kirwin & Fauss, 1909.
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