Barker, Eric, author
Gramedia Pustaka Utama, 2019
Buku Teks
Bryan Lo`s, author
Awesome Books Publishing SDN BHN, 2002
Buku Teks
Maxwell, John C., author
Menuju Insan Cemerlang, 2014
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Covey, Stephen R., author
Simon & Schuster, 2013
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Denning, Melita
Llewellyn Publications, 1993
Buku Teks