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3. Noise From Turbojet Compressors
4. Lilley G. M. and Csanady G. T. On the Vortex Noise from Airscrews, Fans and Compressors. Unpublished paper, 1961.
5. Final Report of the Committee on the Problem of Noise. Cmnd. 2056, H.M.S.O., July 1963.