Bendix, Reinhard
John Wiley, 1964
Buku Teks
McGuire, Edna
Macmillan, 1954
Buku Teks
Russell, Bertrand, 1872-1970
Routledge , 1997
Buku Teks
Platt, Nathaniel
Prentice-Hall, 1964
Buku Teks
edited by Gordon Hughes and Gail Lewis
Routledge, 1998
Buku Teks