Barth, Alan
The Viking Press, 1961
Buku Teks
Newman, Edwin S., author
Oceana Publications,Inc., 1979
Buku Teks
Wagne, Peter, author
Routledge, 1994
Buku Teks
Mill, John Stuart
E.P. Dutton and Company, 1955
Buku Teks
Mill, John Stuart
Yayasan Obor Indonesia, 1996
Buku Teks