Chicago : encyclopaedia Britanica Inc, 2000,
Buku Referensi
Chicago : encyclopaedia Britanica Inc, 1999,
Buku Referensi
Indonesia. Badan Pusat Statistik
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Buku Referensi
Soemitro Djojohadikusumo, author
[publisher not identified], 1975
Buku Teks
Junaidi, author
Faculty of Humanities University of Indonesia, 2002
Artikel Jurnal