Macmillan, 1972
Buku Teks
Scott, James C., author
Yale University Press, 1976
Buku Teks
Loomis, Charles P.
Prentice Hall Inc., 1957
Buku Teks
Scott, James C., author
Yale University Press, 1977
Buku Teks
Popkin, Samuel L., author
Lembaga Penerbit Yayasan Padamu Negeri, 1986
Buku Teks