1. Vlassov V. Thin-walled elastic beams. Israel program for scientific translations Jerusalem; 1961.
2. Methods of analysis for torsion with variable twist;von Krmn;J Aeronaut Sci,1944
3. Torsion with variable twist;von Krmn;J Aeronaut Sci,1949
4. Umansky. Bending and torsion of thin-walled aircraft constructions. Oborongiz, Moskow; 1939.
5. Umansky. On normal stresses in torsion of an aircraft wing. Tekhnika vozdushnogo, Aircraft engineering; 1940.