"Mission of San Diego," in Reports of Explorations and Surveys to Ascertain the Most Practicable and Economical Route for a Railroad from the Mississippi River to the Pacific Ocean, vol. 5, R. S. Williamson, Report of Explorations in California for Railroad Routes, to Connect with the Routes near the 35th and 32nd Parallels of North Latitude. 33rd Cong., 2nd Sess., House Ex. Doc. 91 (Washington, 1856), Serial Set 795.