APA aipamena

(1972). Population and heirarchy of cities and municipalities: Bicol region. [s.n.].

Chicago Style aipamena

Population and Heirarchy of Cities and Municipalities: Bicol Region. [Manila]: [s.n.], 1972.

MLA aipamena

Population and Heirarchy of Cities and Municipalities: Bicol Region. [s.n.], 1972.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.