Wiarda, Howard J., author
Hartcourt College Publishers, 2001
Buku Teks
Beer, Samuel H., author
Alfred A. Knopf, 1966
Buku Teks
Lewis, David, author
Cambridge University Press, 2011
Buku Teks
Sutter, John O., author
Cornell University , 1959
Buku Teks
Stockwin, J.A.A., author
W.W. Norton, 1982
Buku Teks