1. J. F. Knott, “Fundamentals of Fracture Mechanics” (Butterworth, 1973) ch. 4 & 5.
2. P. L. Swanson, C. J. Fairbanks, B. R. Lawn, Y.-W. Mai andB. J. Hockey,J. Amer. Ceram. Soc. 70 (1987) 279.
3. R. M. L. Foote, B. Cotterell andY.-W. Mai, in “Fracture Toughness and Fracture Energy of Concrete”, edited by F. H. Wittman (Elsevier, Amsterdam, 1986) p. 535.
4. P. L. Swanson, PhD thesis, University of Colorado, 1984.
5. A. G. Evans andK. T. Faber,J. Amer. Ceram. Soc. 67 (1984) 255.