Shera, Jesse H.
Archon Books, 1965
Buku Referensi
Rungkat, Thelma
ANCORA Press , 1997
Buku Teks
The University of Chicago Press , 1965
Buku Teks
editor, E. Dale Cluff
The Haworth Press , 1990
Buku Teks
edited by Loriene Roy, Kelly Jensen, Alex Hershey Meyers
[American Management Association, ], 2009
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