Philippines. National Mapping and Resoruce Information Authority. Bontoc. National Mapping and Resource Informatiion Authority, 1988.
Cita Chicago (17th ed.)Philippines. National Mapping and Resoruce Information Authority. Bontoc. Makati, [Metro Manila]: National Mapping and Resource Informatiion Authority, 1988.
Cita MLA (9th ed.)Philippines. National Mapping and Resoruce Information Authority. Bontoc. National Mapping and Resource Informatiion Authority, 1988.
Atenció: Aquestes cites poden no estar 100% correctes.