Fankl, Victor Emil, author
Kreasi Wacana, 2003
Buku Teks
Buring, Daniel, author
Oxford University Press, 2016
Buku Teks
Jackson, Peter, author
Routledge, 1994
Buku Teks
Padover, Saul K. (Saul Kussiel), author
Praeger, 1967
Buku Teks
edited by John Cottingham
Blackwell, 2007
Buku Teks