Belli, Pierin
Oceana Publications Inc, 1964
Buku Teks
Russell, Bertrand, 1872-1970, author
Routledge, 2001
Buku Teks
Pustay, John S.
The Free Press, 1965
Buku Teks
Parson, Nels A.
Cambridge: Harvard University Press, 1962
Buku Teks
Dinniss, Heather Harrison, author
Cambridge University Press, 2012
Buku Teks