The investigation was made by the Geological Survey, U.S. Department of the Interior, starting under the general supervision of J. F. Poland, district geologist in charge of groundwater investigations in California. The final phases of the work were completed under the general supervision of H. D. Wilson, Jr., district engineer, and under the immediate supervision of Fred Kunkel, geologist
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.