Polley, Simon
Taylor &Fransic, 2009
Buku Teks
edited by Sandy Weinberg
Informa Healtcare, 2007
Buku Teks
Edwards, Corwin D.
Ocean Publications , 1966
Buku Teks
by World Health Organiation
World Health Organization, 1974
Buku Teks
Prentice-Hall, 1976
Buku Teks