Humphries, James T.
Breton Publishers, 1983
Buku Teks
Humpries, James T
Delmar Publisher, 1993
Buku Teks
Geddes-Brown, Leslie, author
Pageone , 2002
Buku Referensi
Geddes-Brown, Leslie, author
Page One Publishing, 2002
Buku Referensi
Ganic, Ejup N., author
McGraw-Hill, 2003
Buku Teks