Daniel Belgrad, "'Power's Larger Meaning': The Johnson County War as Political Violence in an Environmental Context," Western Historical Quarterly (2002) 33#2 pp. 159-177 in JSTOR
Oxford University Press No Duty to Retreat: Violence and Values in American History and Society by Richard Maxwell Brown. Product DescriptionArchived 2007-09-29 at the Wayback Machine 1992
Oxford University Press No Duty to Retreat: Violence and Values in American History and Society by Richard Maxwell Brown. Product DescriptionArchived 2007-09-29 at the Wayback Machine 1992
Petrimoutlx, Jim. "U.S. Marshal George A. Wellman (1858-1892)". Bay Journal. Archived from the original on December 4, 2014. Retrieved May 6, 2024. This source gives Wellman's day of death as May 10.