Scale ca. 1:10,000,000. "Map no. 840." "Confidential." Shows period when ports are ice free. LC copy annotated by colored tapes. Typed note pasted on: For Secretary of the Interior Harold L. Ickes from Ruth Gruber. Available also through the Library of Congress Web site as a raster image. Vault AACR2: 650/1; 650/2; 700/1; 710/2
United States. Office Of Strategic Services. Research And Analysis Branch. Geography Division; Ickes, Harold L. (Harold Leclair); United States. Board Of Economic Warfare
1942
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