Philippines. Bureau of Coast and Geodetic Survey. (1940). Northern Luzon, Philippine Islands: Northern sheet. Bureau of Coast and Geodetic Survey.
芝加哥风格引文Philippines. Bureau of Coast and Geodetic Survey. Northern Luzon, Philippine Islands: Northern Sheet. Manila: Bureau of Coast and Geodetic Survey, 1940.
MLA引文Philippines. Bureau of Coast and Geodetic Survey. Northern Luzon, Philippine Islands: Northern Sheet. Bureau of Coast and Geodetic Survey, 1940.
警告：这些引文格式不一定是100％准确.