University of Wisconsin System, 2018
Majalah, Jurnal, Buletin
James A. Johnson
Southern Public Administration Education Foundation, Inc, 1990
Majalah, Jurnal, Buletin
Schmitt, Neal W.
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Jackson, Susan E.
South Westh Western College, 2000
Buku Teks
Sikula, Andrew F.
Wiley, 1976
Buku Teks