editors, George E. Haggerty, Molly McGarry
Wiley Balckwell, 2015
Buku Teks
Jodie Medd
Cambridge University Press, 2012
eBooks
Huxley, Julian, compiler
London Penguin 1937
Buku Teks
Lynch, Gordon
Blackwell Publishing, 2005
Buku Teks
Storey, John, 1950-
Prentice-Hall, 2000
Buku Teks