Texas. Legislature. House of Representatives. 78th Texas Legislature, Regular Session, House Bill 453, Chapter 434, legislative document, 2003-05/2003-06; (https://texashistory.unt.edu/ark:/67531/metapth158712/m1/1/: accessed August 21, 2018), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .