グリネル (アイオワ州)
Grinnell College. 2012年2月8日.
↑ Morgan, J. "The Development of Sociology and the Social Gospel in America". pp.42-53. Sociological Analysis. Vol.30. Issue 1. Oxford University Press. 1969年. doi: 10.2307/3709933. JSTOR 3709933.
↑ Robert, Handy. "George D. Herron and the Kingdom Movement". pp.97-115. Church History. Vol.19. Issue 2. American Society of Church History. 1950年. doi: 10.2307/3162192. JSTOR 3162192.
1 2 Cavanagh, Lynn and Mary Schuchmann, pp.93-95.
↑ Grazulis, Thomas P. The Most "Important" US Tornadoes by State (アーカイブ). 2016年3月4日.
↑ Grazulis, Thomas P. Significant Tornadoes 1680–1991: A Chronology and Analysis of Events. St. Johnsbury, Vermont: The Tornado Project of Environmental Films. 1993年7月. ISBN 1-879362-03-1.
↑ Beitler, Stu.