edited by John K. Ryan
The Catholic University of America Press, 1963
Buku Teks SO
Stumpf, Samuel Enoch, 1918-1998
McGraw-Hill, 1971
Buku Teks SO
edited by F.S.C. Northrop
Yale University Press, 1949
Buku Teks SO
Patrick, George Thomas White
George Allen and Unwin, 1925
Buku Teks SO
Russell, Bertrand, 1872-1970
Oxford University Press, 1912
Buku Teks SO