Pagels, Heinz R.
Simon and Schuster , 1988
Buku Teks SO
Mainzer, Klaus
Springer, 2012
eBooks
Corbett, Sister Thomas Albert
University of America Press, 1950
Buku Teks
Mey, Marc De
Dordrecht, 1982
Buku Teks SO
edited and with an introd. by Arnold B. Arons [and] Alfred M. Bork
Prentice-Hall, 1964
Buku Teks SO