Becker, Joanne M.
Delmar Cengage Learning, 2010
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Charlene Davis
Entrepreneur Press, 2012
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Nigel Raby, Laurence Berman, Simon Morley, Gerald de Lacey
Elsevier, 2015
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The Reader's Digest Association, Inc, 1998
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Wolters Kluwer Health
Lippincott Williams & Wilkins, 2013
Buku Teks SO