Texas. Legislature. House of Representatives. 82nd Texas Legislature, Regular Session, House Bill 260, Chapter 223, legislative document, June 17, 2011; (https://texashistory.unt.edu/ark:/67531/metapth311320/m1/1/: accessed December 13, 2018), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .