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Buku Teks
Howarth, David, author
McGraw-Hill, 1966
Buku Teks
Collazos, Sharon Phillipps
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Buku Teks
Tampubolon, Murlania, author
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 2004
UI - Skripsi (Membership)
Blais, Marie-Claire, 1939-, author
McClelland and Stewart, 1979
Buku Teks