Slavery in the territories : speech of Hon. J. Thompson, of Mississippi. In the House of Representatives, June 27, 1848., pamphlet, 1848; (https://texashistory.unt.edu/ark:/67531/metapth498634/m1/1/: accessed July 18, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .