Brown, Lawrence D.
Business Publications, 1987
Buku Teks
Gibson, Charles H.
South Western College , 2001
Buku Teks
Bellandi, Francesco
Emerald, 2018
eBooks
Joo, Jalaleddin Soroosh
UMI research Press, 1982
Buku Teks
Modern Business Report , 1985
Buku Teks