Feigin, Gerald, author
Business Expert Press, 2011
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Peters, Thomas J.
Harper & Row, Publishers, 1986
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Anindya Kirana Widowati, author
Fakultas Ilmu Keperawatan Universitas Indonesia, 2022
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Ryan, Thomas Arthur
The Ronald Company , 1954
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Kendrick, Tom, author
American Management Association, 2004
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