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Buku Teks
Baruss, Imants, author
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Buku Teks
Collins, John Edward, author
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Buku Teks
Wojciechowski, Jerzy A., author
Council for research in values and philosophy, [Date of publication not identified]
Buku Teks SO
Julizar Firmansyah, author
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 2003
UI - Tesis Membership