Philippines. Bureau of Coast and Geodetic Survey. (1940). Northern Luzon, Philippine Islands: Northern sheet. Bureau of Coast and Geodetic Survey.
Chicago-viite (17. p.)Philippines. Bureau of Coast and Geodetic Survey. Northern Luzon, Philippine Islands: Northern Sheet. Manila: Bureau of Coast and Geodetic Survey, 1940.
MLA-viite (9. p.)Philippines. Bureau of Coast and Geodetic Survey. Northern Luzon, Philippine Islands: Northern Sheet. Bureau of Coast and Geodetic Survey, 1940.
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