United States. Bureau of the Census. P.L. 94-171 County Block Map (2010 Census): Gillespie County, Block 20, map, December 14, 2010; (https://texashistory.unt.edu/ark:/67531/metapth386279/m1/1/: accessed May 2, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .