Von der Mehden, Fred R., author
Prentice-Hall, 1969
Buku Teks
Von der Mehden, Fred R., author
Prentice-Hall, 1964
Buku Teks
Duchacek, Ivo D., author
Dryden Press, 1971
Buku Teks
Magstadt, Thomas M., author
Thomson wadsworth, 2005
Buku Teks
Underhill, Frank H., author
Duke University Press, 1956
Buku Teks