Schoch, Elizabeth T.
Adam Media Corporation, 2002
Buku Teks
Springer, 2012
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Warren, Bruce, author
Wadsworth and Cengage Learning, 2013
Buku Teks
Muhammad Farhan Pristantyo, author
Fakultas Teknik Universitas Indonesia , 2021
UI - Skripsi (Membership)
Sinclair, Joseph T., author
American Management Association, 2005
eBooks