1. Harriette D. Walker to Mary Baker Eddy, 21 October 1885, https://mbepapers.org/?load=721AP1.88.029.
  2. Solomon W. Straub to Mary Baker Eddy, 2 June 1884, https://mbepapers.org/?load=952.93.040.
  3. Hash, Phillip M. “Solomon W. Straub (1842–1899): A Self-Made Music Educator on the Prairie.” Journal of Historical Research in Music Education 37, no. 1 (2015): 51–74. Accessed 7 May 2021. https://www.jstor.org/stable/26376894.
  4. J. Newton Stone to Mary Baker Eddy, 7 January 1886, https://mbepapers.org/?load=577.59.007.
  5. J. Allen and Lysbeth L. Campbell to Mary Baker Eddy, 22 October 1885, https://mbepapers.org/?load=528.57.009.