Contributions from the United States National Herbarium - United States. National Herbarium. (Smithsonian Institution Press, 1925)

A flora of California - Jepson, Willis Linn, 1867 -1946 (Cunningham, Curtis & Welch, 1909)

An illustrated flora of the Pacific States: Washington, Oregon, and California - Abrams, Le Roy, 1874 -1956 (Stanford University Press, 1951)