Kean, John M.
St. Martin's Press , 1976
Buku Teks
Ben-Chai, David, author
Sense, 2012
eBooks
Tinker, Miles A., author
Appleton-Century-Crofts, 1962
Buku Teks
Burns, Paul C., author
Houghton Miffiln, 1984
Buku Teks
edited by John Sears and Pete Sorensen
Routledge Falmer, 2000
Buku Teks