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Thomson Wadsworth, 2003

 Buku Teks

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Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 2013

 UI - Disertasi (Membership)

Jane Picford, editor

Cavendish Publishing , 2000

 Buku Teks

Arrigo, Bruce A., author

West/Wadsworth, 1999

 Buku Teks

Pieper, Josef, author

Pantheon Books, 1955

 Buku Teks