Balmori, Diana
Yale University Press, 1993
Buku Teks
Stefferud, Alfred, editor
United States. Government Printing Office, 1966
Buku Referensi
Wood, Julia T., 1950-, author
Wadsworth and Cengage Learning, 2012
Buku Teks
Schramm, Wilbur, author
Standford University Press, 1961
Buku Teks
Dunn, James A.
MIT Press, 1981
Buku Teks