Philippines (Republic). Bureau of the Census and Statistics. Report. [s.n.
Chicago-referens (17:e uppl.)Philippines (Republic). Bureau of the Census and Statistics. Report. Manila: [s.n.
MLA-referens (9:e uppl.)Philippines (Republic). Bureau of the Census and Statistics. Report. [s.n.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.