Keuth, Herbert
The Philosophy karl Popper / Herbert Keuth
Cambridge University Press, 2005
 Buku Teks SO
Keuth, Herbert, 1940-
The philosophy of Karl Popper / Herbert Keuth
Cambridge University Press, 2005
 Buku Teks SO
Studies in Philosophy And The History of philosophy
edited by John K. Ryan
The Catholic University of America Press, 1963
 Buku Teks SO
Patrick, George Thomas White
Introduction to philosophy
George Allen and Unwin, 1925
 Buku Teks SO
Russell, Bertrand, 1872-1970
The problems of philosophy
Oxford University Press, 1912
 Buku Teks SO