Gist, Noel P.
Harper & Row , 1974
Buku Teks SO
Mercer, Charles
Penguin Books, 1975
Buku Teks SO
Cousins, Albert N., 1919-
John Wiley & Sons, 1979
Buku Teks SO
Porteous, J. Douglas
Addison-Wesley, 1977
Buku Teks SO
Dushkin/McGraw-Hill , 1999
Buku Teks SO