Frank C Calkins, Dallas L Peck, and Clyde Wahrhaftig (1962)
Road log 3, El Portal to Wawona Tunnel and a circuit of Yosemite Valley, California
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Citation found in GeoRef database ProCite field[9]: Geologic guide to the Merced Canyon and Yosemite Valley, California. California Division of Mines and Geology Bulletin ProCite field[26]: p. 661-668