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UI - Skripsi (Membership)
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Buku Teks
edited by Richard Lord [and others]
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Buku Teks
Lubis, H. T. Hanun, author
Universitas Indonesia, 1985
UI - Skripsi (Membership)
Marpaung, Leden, author
Sinar Grafika, 1997
Buku Teks