Knapton, James
Random House, 1967
Buku Teks
Fred Genesee, Kathryn Lindholm-Leary, William M. Saunders, Donna Christian
Cambridge University Press, 2008
Buku Teks SO
Griffith, Peter
Open University Press, 1991
Buku Teks SO
Bryson, Bethany
Stanford University Press, 2005
Buku Teks
edited by Fred Genesee ...[et al.]
Cambridge University Press, 2006
Buku Teks SO