[CALIFORNIA]. Summary of Operations, California Oil Fields. San Francisco: State of California Department of Natural Resources, 1929. 8vo. Together, 8 quarterly and monthly reports in 2 volumes, comprising: Vol. 14 No. 7 (Jan. 1929)?V14 No. 12 (June 1929); and Vol. 15 No. 1 (July/Aug/Sept, 1929)?Vol. 15 No. 2 (Oct./Nov./Dec., 1929). Illustrated with folding maps, graphs, charts, and tables. Contemporary black buckram with marbled sides (one volume cracked with defective hinges; some chipping to edges but clean overall).