Manz, K. G. [Letter from K. G. Manz to R. C. Gaertner, April 14, 1928], letter, April 14, 1926; (https://texashistory.unt.edu/ark:/67531/metapth591375/m1/1/: accessed July 3, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu.; .