United States. Bureau of the Census. 1990 Census County Block Map (Recreated): Yoakum County, Block 2, map, 1990; (https://texashistory.unt.edu/ark:/67531/metapth358597/m1/1/: accessed December 18, 2018), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .