Wei Choo, Chun
Oxford university press, 1998
Buku Teks
Chun, Wei Choo
Oxford university press, 1998
Buku Teks
May, John
McGraw-Hill , 1983
Buku Teks
edited by Linda L. Putnam, Michael E. Pacanowsky
Sage, 1983
Buku Teks
Machin, John L.J., author
McGraw-Hill, 1980
Buku Teks