The encyclopedia of philosophy
editor, Donald M. Borchert
Macmilan, 1996
 Buku Referensi
Concise Routledge encyclopedia of philosophy
Routledge, 2000
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The encyclopedia of philosophy volume 7 and 8
Paul Edwards, editor in chief
Macmilan , 1972
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The encyclopedia of philosophy: volumes 1 and 2
editor, Paul Edwards
MacMilan, 1972
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The Encyclopedia of philosophy: volumes 5 and 6
editor in chief Paul Edward
MacMilan, 1972
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