Popper, Karl R., author
LP3ES, 1985
Buku Teks
Krishnamurti, J. (Jiddu), 1895-1986, author
Yayasan Krisnamurti Indonesia, 2008
Buku Teks
Osborn, Alex
Charles Scribner`s Sons, 1952
Buku Teks
Russell, Bertrand, 1872-1970, author
George Allen and Unwin, 1956
Buku Teks
Bury, J. B.
Yajasan Pembangunan, 1951
Buku Teks