Copy of a letter from Joseph Needham to Sir Frederick Handley Page of London, enquiring about his knowledge of the fenestrated rudder on Chinese junks as the possible ancestor of the slotted wing of aircraft, and related documents, 1952-03-02 - 1952-03-31, GBR/1928/NRI/SCC2/124/5/2. The Papers and Possessions of Joseph Needham, GBR/1928/NRI/NRI2. Needham Research Institute. https://archivesearch.lib.cam.ac.uk/repositories/21/archival_objects/347135 Accessed May 21, 2025.