Begin the citation with the publisher's name followed by the word "Cartographer" in parentheses. For example, "U.S. Census Bureau Maps and Cartographic Resources (Cartographer)."
Give the date the map was published in parentheses -- for example, "(2008)."
List the title of the map followed by the type of the map within square brackets -- such as "[demographic map]" or "[topographic map]." For example, "Combined statistical areas of the United States and Puerto Rico, November 2008 [statistical map]."
Give the URL if you retrieved the map from a Website. Use the format "Retrieved from URL" and do not use a period after the URL: for example, "Retrieved from http://www.census.gov/geo/www/maps/msa_maps2008/us_wall_1108.html".