Cite

State Highway Department's map of the state of Oregon showing main traveled automobile roads / Oregon State Highway Commission.

MLA

Commission, Oregon State Highway. State Highway Department's Map of the State of Oregon Showing Main Traveled Automobile Roads / Oregon State Highway Commission. Oregon State Highway Commission, 1946. https://collections.library.yale.edu/catalog/15821618.

APA, 6th edition

Commission, O. S. H. (1946). State Highway Department's map of the state of Oregon showing main traveled automobile roads / Oregon State Highway Commission. [Road maps]. Oregon State Highway Commission, https://collections.library.yale.edu/catalog/15821618.