Hopper, Richard Hutchinson (1939) A Geologic Section from the Sierra Nevada to Death Valley, California (Dissertation (Ph.D)), California Institute of Technology doi: 10.7907/0HXX-FR95 Bryson, Robert PearneHopper, Richard Hutchinson (1937) Magnetic Studies in the Inglewood District (Thesis (Masters)), California Institute of Technology doi: 10.7907/ngdy-zj23