Rader, Melvin
The enduring questions; main problems of philosophy / Melvin Rader.
Holt, Rinehart and Winston, 1966
 Buku Teks
Man and philosophy: German opinion on problems of today
editor, Walter Leifer
Max Hueber verlag, Muchen, 1964
 Buku Teks
Man and philosophy: German opinion on problems of today
editor, Walter Leifer
Max Hueber verlag, Muchen, 1964
 Buku Teks
Rachels, James, 1941-2003
Problems from philosophy
McGraw-Hill, 2012
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Stumpf, Samuel Enoch, 1918-1998
Philosophy history and problems
McGraw-Hill, 1989
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