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Published 2002
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Published 2002
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Published 2010
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Published 2010
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Published 2009
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Published 2006
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Published 2003
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by Ong, Loo Chen
Published 2005
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Published 2003
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Published 1998
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Published 2004
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Published 2002
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Published 2009
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Published 2008
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Published 2006
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Published 2004
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