[Bas-relief of Wilhelm Roentgen], photograph, Date Unknown; (https://texashistory.unt.edu/ark:/67531/metapth1161591/m1/1/: accessed June 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .
[Bas-relief of Wilhelm Roentgen], photograph, Date Unknown; (https://texashistory.unt.edu/ark:/67531/metapth1161591/m1/1/: accessed June 16, 2024), University of North Texas Libraries, The Portal to Texas History, texashistory.unt.edu; .