Gaya APA
Valenzuela, A, V., al, E. (1983).
Illness prevalence survey 3 municipalites in the Philippines 1982-1983 .
Jakarta:
ASEAN.
Gaya MLA
Valenzuela, Amanda, V.., al, Et.
"Illness prevalence survey 3 municipalites in the Philippines 1982-1983".
Jakarta:
ASEAN,
1983.
print.