Bonevac, Daniel
McGraw-Hill, 2002
Buku Teks
Banner, Michael
Cambridge Unuversity Press , 1999
Buku Teks
edited by Christopher W. Gowans
Routledge, 2000
Buku Teks
Markham, Ian S.
Blackwell, 2007
Buku Teks
edited by Samuel Gorovitz ... [et al.]
Prentice-Hall, 1976
Buku Teks