1. V. V. Panasyuk, Limit Equilibrium of Brittle Bodies with Cracks [in Russian], Naukova Dumka, Kiev (1968).
2. G. Ya. Popov, Concentration of Elastic Stresses Next to Punches, slits, Fine Inclusions, and Reinforcements [in Russian], Nauka, Moscow (1982).
3. V. I. Fabrikant, “Flat crack of arbitrary shape in an elastic space,” Philos. Mag. A,56, No. 2, 175–189 (1987).
4. J. R. Rice, “First-order variation in elastic fields due to variation in location of a plane crack front,” Trans. ASME: J. Appl. Mech.,52, No. 3, 571–579 (1985).
5. N. M. Borodachev, “One variational method of solving the spatial problem of the theory of elasticity for a body with a flat crack,” Prikl. Mekh.,22, No. 4, 71–76 (1986).