Não informado. Summary of operations, California oil fields. Department of Natural Resources, Division of Oil and Gas.
Chicago-viite (17. p.)Não informado. Summary of Operations, California Oil Fields. San Francisco, Calif: Department of Natural Resources, Division of Oil and Gas.
MLA-viite (8. p.)Não informado. Summary of Operations, California Oil Fields. Department of Natural Resources, Division of Oil and Gas.
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