World Health Organization, 1988
Buku Teks
Bury, Michael, author
Routledge, 2000
Buku Teks
Ducanis, Alex J., author
Aspen Publication, 1979
Buku Teks
Englebardt, Sheila P., author
Mosby , 2002
Buku Teks
edited by Joseph M. Kasonde and John D. Martin
World Health Organization, 1994
Buku Teks