Gonzalez, Andrew B., author
Oxford University Press, 1984
Buku Teks SO
edited by Richard B. Noss
SEAMEO Regional Language Centre, 1982
Buku Teks SO
Summer Institute of Linguistics (Philippines) : Linguistic Society of the Philippines, 1981
Buku Teks SO
WHO
WHO, 2006
Buku Teks
The University Press of Hawaii, 1976
Buku Teks