Sheed and Ward , 1966
Buku Teks
Gelles, Richard J., author
McGraw-Hill College , 1999
Buku Teks
Schrag, Clarence C., author
Harper & Row, 1963
Buku Teks
Zanden, James W. Vander, author
John Wiley & Sons, 1979
Buku Teks
Ogburn, William F., author
Houghton Mifflin, 1946
Buku Teks