Lagomarcino, John P. [Letter from John P. Lagomarcino to John J. Herrera - 1968-04-24], letter, April 24, 1968; (https://texashistory.unt.edu/ark:/67531/metapth248853/m1/1/: accessed February 23, 2020), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .