Raymond W. Cox III
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Buku Teks SO
edited by Alan Montefiore and David Vines
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Buku Teks SO
Dunleavy, Patrick
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Buku Teks
Mosher, Frederick C.
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Buku Teks
edited by Tinatin Bocorivili; Sweet William; Daniel Ahern
Council for Research in Values and Philosophy, 2005
Buku Teks SO