1. (4) Bickley W. G. Critical conditions for compressible flow (Aeronautical Research Committee, no. 9657).
2. (3) Lighthill M. J. The hodograph transformation in trans-sonic flow. (1) Symmetrical channels (Aeronautical Research Committee, no. 9856).
3. (1) Craggs J. W. The application of the hodograph method to problems of subsonic compressible flow in two dimensions (Aeronautical Research Committee, no. 9801).
4. Grenzlinien adiabatischer Potentialströmungen