Hirsch, Eric Donald, Jr., author
Yale University Press, 1976
Buku Teks
Barnett, Nancy Smith, author
Prentice-Hall, 1972
Buku Teks
Ferguson, C. E., author
Duke University Press, 1964
Buku Teks
Vane, Howard R., author
Harvester Wheatsheaf , 1989
Buku Teks
Vane, Howard R., author
Harvester Wheatsheaf , 1993
Buku Teks