Greasley, Andrew
Stanley Thornes, 1999
Buku Teks
Chase, Richard B., author
McGraw-Hill, 2001
Buku Teks
Bozzone, Vincent, author
[American Management Association, ], 2002
eBooks
Syaiful Wahdi, author
Fakultas Teknik Universitas Indonesia, 1999
UI - Skripsi (Membership)
Rage, Louis J., author
Scranton, Penn., International Textbook
Buku Teks