edited by Mildred Kaufman
An Aspen Publication, 1990
Buku Referensi
Bee, Helen L.
Allyn and Bacon, 2010
Buku Teks
King, Felicity Savage
Oxford University Press, 1995
Buku Teks
Holden, Chris
Bailliere Tindall , 2000
Buku Teks
Heimburger, Douglas C.
Mosby, Elsevier, 2006
Buku Referensi