Wenger, F. H.; Hiebert, Clarence (1989). "Holdeman, John (1832-1900)". Global Anabaptist Mennonite Encyclopedia Online. GAMEO. Retrieved August 30, 2016.
Hiebert, P. G.; Hiebert, Clarence (1990). "Church of God in Christ, Mennonite (CGC)". Global Anabaptist Mennonite Encyclopedia Online. GAMEO. Retrieved August 30, 2016.