Hocking, William Ernest
Harpers and Brothers Publisher, 1956
Buku Teks
Willener, Alfred
Pantheon Books, 1970
Buku Teks
Drucker, Peter F. (Peter Ferdinand), 1909-2005, author
Harper & Brothers, 1959
Buku Teks
Inkeles, Alex
Harvard University Press, 1974
Buku Teks
Krutch, Joseph Wood, author
Greenwood Press, 1979
Buku Teks