APA

Pearl R. M., McGraw-Hill Companies, . (1951). Guide to geologic literature. New York [etc.]: McGraw-Hill Book Company, Inc.

Chicago

Pearl Richard Maxwell, McGraw-Hill Companies, . 1951. Guide to geologic literature. New York [etc.]: McGraw-Hill Book Company, Inc.

Harvard

Pearl R. M., McGraw-Hill Companies, . (1951). Guide to geologic literature. New York [etc.]: McGraw-Hill Book Company, Inc.

MLA

Pearl Richard Maxwell, McGraw-Hill Companies, . Guide to geologic literature. New York [etc.]: McGraw-Hill Book Company, Inc. 1951.