1. U. Brown and J. Srawley, Fracture-Toughness Tests of High-Strength Metallic Materials Plane Strain [Russian translation], Mir (1970), p. 246.
2. in: New Methods of Evaluating the Resistance of Materials to Brittle Fracture (edited by Yu. N. Rabotnov) [Russian translation], Mir (1972).
3. Yu. N. Rabotnov, Izv. Akad. Nauk SSSR, Otd. Tekh. Nauk, Mekh. Mashinostr., No. 2, 3?11 (1962).
4. G. P. Cherepanov, Brittle-Fracture Mechanics [in Russian], Nauka (1974).
5. M. Ya. Leonov and V. V. Panasyuk, Prikl. Mekh., No. 4, 391?397 (1959).