Dunning, John H.
George Allen and Unwin , 1974
Buku Teks
edited by Huub Ruel
Emerald, 2018
eBooks
Cullen, John Brooks, 1948-
Thomson, 2005
Buku Teks
Michael R. Czinkota, Ronkainen Ilkka A., Michael H.Moffett, Eugene O. Moynihan, ... [et al.].
Harcourt College publishers, 2001
Buku Teks
Pettinger, Richard
Capstone Publishing, 2002
Buku Teks