Snowden, Lynne L., author
Pearson-Prentice Hall, 2005
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Rifdah Azzahra, author
2019
UI - Makalah dan Kertas Kerja
edited by Abdul Rashid Moten and Noraini M. Noor
Thomson , 2007
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Stern, Jessica, author
An Imprint of Harper Collins Publishers, 2003
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Lentini, Pete, author
Edward Elgar, 2013
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