O`Brien, Dan, author
Polity Press, 2006
Buku Teks
Rescher, Nicholas, author
State University of New York Press, 2003
Buku Teks
Audi, Robert, author
Routledge, 2011
Buku Teks
Dicker, Georges, author
Oxford University Press , 2004
Buku Teks
Morton, Adam, author
Blackwell, 1997
Buku Teks