1. Timoshenko, S. P.: History of the Strength of Materials, p. 51. New York: McGraw-Hill 1953.
2. Nadai, A.: Theory of Flow and Fracture of Solids, pp. 207–228. New York: McGraw-Hill 1950.
3. Griffith, A. A.: The Phenomenon of Rupture and Flow in Solids. Phil. Trans. Roy. Soc. Lond., Ser. A 221, 163–198 (1920).
4. Weibull, W.: A Statistical Theory of the Strength of Metals. Proc. Roy. Swed. Inst. Eng. Res. 1939, No. 151.
5. Westergaard, H. M.: Bearing Pressure and Cracks. J. Appl. Mech. 6 (2) (1939).