MLA

Grayson, James H. Pathfinder Map : California, Arizona, New Mexico, Utah, Nevada / [Prepared for] Pathfinder Petroleum Company, Los Angeles. James H. Grayson?, 1942. https://collections.library.yale.edu/catalog/15821497.

APA, 6th edition

Grayson, J. H. (1942). Pathfinder map : California, Arizona, New Mexico, Utah, Nevada / [Prepared for] Pathfinder Petroleum Company, Los Angeles. [Road maps]. James H. Grayson?, https://collections.library.yale.edu/catalog/15821497.