1. J. A. Begley and J. D. Landes, Fracture Toughness, STP 514, American Society for Testing and Materials, Philadelphia (1972) 1–20.
2. J. D. Landes and J. A. Begley, op. cit., 24–39.
3. J. D. Landes and J. A. Begley, Fracture Analysis, STP 560, American Society for Testing and Materials, Philadelphia (1974) 170–186.
4. W. A. Logsdon, Mechanics of Crack Growth, STP 590, American Society for Testing and Materials, Philadelphia (1976) 43–60.