Eighth International Conference of the International Committee for Bird Preservation, Uppsala, 8-10 Jun 1950; Tenth International Ornithological Congress, Uppsala, Sweden, 10-17 Jun 1950.

Nicholson attended both conferences and gave a paper entitled 'Birds of the North Atlantic' on 16th Jun.

Typescript notes by Nicholson chiefly on topics and points presented at the Tenth International Ornithological Congress; typescript report by Nicholson on the two Uppsala conferences, headed 'Nature Conservancy' and apparently prepared for a committee meeting; Swedish newspaper report on the IOC Congress; letter to Nicholson arising.