Alcorn-Oppedahl, Allison A. (Allison Ann). Mail Order Music: the Hinners Organ Company in the Dakotas, 1879-1936, dissertation, August 1997; (https://digital.library.unt.edu/ark:/67531/metadc278307/m1/1/: accessed September 23, 2017), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .