| United States. Office of Indian Affairs. Matches 2 items |
| United States Office of Lend-Lease Administration. Matches 1 item |
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United States. Office of Military History. SEE: United States. Department of the Army. Office of Military History Matches 1 item
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United States. Office of Naval Operations. SEE: United States. Office of the Chief of Naval Operations Matches 1 item
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| United States. Office of Naval Records and Library. Matches 1 item |
| United States. Office of Naval Research. Matches 2 items |
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United States. Office of Naval Research, Science, and Technologies. SEE: United States. Office of Naval Research Matches 2 items
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United States. Office of Naval War Records. SEE: United States. Naval War Records Office Matches 1 item
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United States. Office of Technology Assessment. SEE: United States. Congress. Office of Technology Assessment Matches 2 items
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United States. Office of the Chief of Military History. SEE: United States. Department of the Army. Office of Military History Matches 1 item
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