Patrick, George Thomas White
Introduction to philosophy
George Allen and Unwin, 1925
 Buku Teks SO
Brightman, Edgar Sheffield
An Introduction to philosophy
Holt, Rinehart and Winston, 1961
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Randall, John Herman
Philosophy : an introduction
Barnes & Noble, 1957
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Concise Routledge encyclopedia of philosophy
Routledge, 2000
 Buku Referensi
Luce, J.V.
An introduction to greek philosophy
Thames and Hudson, 1994
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