Daniels, Kathy
Chartered Institute of Personnel and Development, 2012
Buku Teks
Presser, Stephen B.
Thomson/West, 2010
Buku Teks
Madura, Jeff
South-Western College, 2001
Buku Teks
Cunningham, William H.
South-Western, 1984
Buku Teks
Pride, William M.
South Western Cengage Learning, 2012
Buku Teks