Kelly, Curtis, author
Cambridge university press, 2008
Buku Teks
Kelly, Curtis, author
Cambridge university press, 2010
Buku Teks
Spaventa, Lou J., author
McGraw-Hill, 2001
Buku Teks
Presley, John W., author
Holt, Rinehart and Winston, 1980
Buku Teks
Steven, Laurence, author
Prentice-Hall, 1999
Buku Teks