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Buku Teks
O`Day, Rosemary
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Buku Teks
Siojang, H. Baso
Sulawesi Tengah: P-2 NB, 1998,
Buku Teks
Universitas Indonesia, 2006
UI - Skripsi (Membership)
Nasution, Zulkarimein, author
1976
UI - Skripsi (Membership)