2004. Instituto Nacional de Estadística, Geografía e Informática (Mexico), Geological Survey (U.S.), and Canada Centre for Remote Sensing. This line shapefile represents roads in North America at 1:1,000,000 scale. The roads included in this layer are either those that connect major ce... Geological Survey (U.S.).
2011. United States. Bureau of Transportation Statistics, Beningo, Steve, United States. Bureau of Customs and Border Protection, and Liu, Zhi. This point shapefile depicts points of entry for land modes along the United States - Canada border and the United States - Mexico border. The port... United States. Bureau of Transportation Statistics.