Reid, J. H. Stewart
Longmans, Green and Co. , 1959
Buku Teks
Hutheesing, Raja
Orient Longmans,, 1960
Buku Teks
Hamilton, Mark
Neo-tech books, 2000
Buku Teks
National Committee for the Tenth Conference of Heads of State or Government of Non-Aligned Countries
Gramedia Pustaka Utama, 1992
Buku Teks
World Health Organization
World Health Organization, 1976
Buku Teks