Webster, Andrew, author
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Buku Teks
edited by Michael M. Cernea
Oxford Universiy Press, 1985
Buku Referensi
Long, Norman, author
Tavistock Publication, 1980
Buku Teks
Seda, Francisia Saveria Sika Ery, author
UI-Press, 2014
Buku Teks
Yogi Vidyattama, author
2006
Artikel Jurnal