Andrews, Deborah C.
Macmillan Publishing Company, 1988
Buku Teks
Holt, Rinehart and Winston of Canada, Limited, 1988
Buku Teks
Locker, Kitty O., author
McGraw-Hill, 2009
Buku Teks
Goodall, H. Lloyd., author
Wadsworth and Cengage Learning, 2010
Buku Teks
Young, Dona J., author
McGraw-Hill, 2006
Buku Teks