Thompson, Joyce Beebe, author
Macmillan, 1981
Buku Teks
Healey, Edwin F., author
Loyola University Press, 1956
Buku Teks
Edel, May
Charles C. Thomas, 1959
Buku Teks
Keeble, Richard, author
Routledge , 2009
Buku Teks
Floridi, Luciano, 1964-, author
Oxford University Press, 2015
Buku Teks