Anggleton, Peter, Chase, Elaine, Rivers, Kim, Toft, Marlyn, Tyrer, Paul, Warwick, Ian, Whitty, Geoff
Churchill Livingstone , 1994
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Aggleton, Peter
London : Churchill Livingstone Inc., 1994,
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Artikel Jurnal
Fan, Hung, author
Jones And Bartlett Publishers, 2003
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Harahap, Syaiful W, author
Pustaka Sinar Harapan, 2000
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