Berkowitz, Gerald M., author
Longman, 1994
Buku Teks
Downer, Alan, author
University of Minnesota Press, 1961
Buku Teks
edited by Edmund S. Morgan
Prentice-Hall, 1965
Buku Teks
Baur, John I.H. (John Ireland Howe), 1909-1987, author
Harvard University Press, 1951
Buku Teks
Jones, Howard, author
Franklin Watt , 1985
Buku Teks