Manser, W.A.P.
Cassell/Associated Business Programmes, 1973
Buku Teks
Sethi, S. Prakash, author
Goodyear, 1973
Buku Teks
Vernon, Raymond, author
Harvard University Press, 1972
Buku Teks
Steiner, George A. (George Albert), 1912-, author
Macmillan, 1966
Buku Teks
Turner, Louis
Hamish Hamilton , 1970
Buku Teks