Wright, Andrew, 1937-, author
Cambridge University Press , 1989
Buku Teks
Forfar, Colin, author
Helath Press, 1995
Buku Teks
Eliot, Alexander
Time Incerperated, 1963
Buku Teks
Moncrieff, A.R. Hope, author
Gramercy Books, 1995
Buku Referensi
Sealey, Raphael, author
University of North Carolina Press, 1990
Buku Teks