Burton, Sharon
Houghton-Mifflin, 1992
Buku Teks
Baird, Colin
W.H. Freemen and Company , 2008
Buku Teks
Miller, G. Tyler (George Tyler), 1931-
Brooks/Cole. Cengage Learning, 2009
Buku Teks
Scuzzo, Giuseppe
Quintessenz Verlag, 2003
Buku Teks
MacKenthun, Kenneth M.
Lewis Publishers, 1998
Buku Teks