Agger, Robert E.
N.Y. John-Wiley , 1966
Buku Teks
Dye, Thomas R., author
Prentice_Hall, Inc, 1988
Buku Teks
Adrian, Charles R., author
McGraw-Hill , 1978
Buku Teks
Judd, Dennis R., author
Little, Brown, 1979
Buku Teks
OConnor, Karen, author
Addison Wesley Longman, 2001
Buku Teks