Bacal, Robert
McGraw-Hill, 2004
Buku Referensi
Nilson, Carolyn
[American Management Association, ], 2003
eBooks
Nilson, Carolyn
[American Management Association;, ], 2007
eBooks
Mather, Hal
McGraw-Hill, 1984
Buku Teks
Pickering, Peg
Erlangga, 2001
Buku Teks