Simpson, J. H. 1. (1865). Report of Lieut. Col. James H. Simpson ...: On the Union Pacific Railroad and branches, Central Pacific Railroad of California, Northern Pacific Railroad, wagon roads in the territories of Idaho, Montana, Dakota, and Nebraska, and the Washington Aqueduct. Washington: Govt. print. off..

Simpson, J. H. 1813-1883. Report of Lieut. Col. James H. Simpson ...: On the Union Pacific Railroad and Branches, Central Pacific Railroad of California, Northern Pacific Railroad, Wagon Roads in the Territories of Idaho, Montana, Dakota, and Nebraska, and the Washington Aqueduct. Washington: Govt. print. off., 1865.

Simpson, J. H. 1813-1883. Report of Lieut. Col. James H. Simpson ...: On the Union Pacific Railroad and Branches, Central Pacific Railroad of California, Northern Pacific Railroad, Wagon Roads in the Territories of Idaho, Montana, Dakota, and Nebraska, and the Washington Aqueduct. Washington: Govt. print. off., 1865.