Donaldson, Cam
Macmillan, 1994
Buku Teks
Cooper, Michael H.
John Wiley & Sons, 1975
Buku Teks
Phelps, Charles E.
Harper Collins, 1992
Buku Teks
Antezana, Fernando
World Health Organization, 1996
Buku Teks
Wonderling, David
Open University Press, 2005
Buku Teks