Luhr, William, author
Putnam, 1977
Buku Teks
Osborne, Harold
London Routledge & Kegan Paul 1955
Buku Teks
edited by Matthew Kieran
Blackwell, 2006
Buku Teks
London Routledge , 1992
Buku Teks
edited by Susan L. Feagin and Patrick Mayhard
Oxford University Press, 1997
Buku Teks