Collins, Randall, author
Oxford University Press , 1992
Buku Teks
Currier, Glenn
Harcourt, college Pub., 1997
Buku Teks
Giddens, Anthony, author
W.W. Norton & Compan, 2005
Buku Teks
Tischler, Henry L.
Wadsworth and Cengage Learning, 2014
Buku Teks
Mckee, James B., author
Holt, Rinehart and Winston, 1969
Buku Teks