1. Crack depth measurement with surface waves;Cook,1972
2. Non-destructive measurement of the depth of surface-breaking cracks using ultrasonic waves;Hudgell;British Journal of NDT,1974
3. Krautkramer, J. & H. Ultrasonic testing of materials (Heidelberg, New York)
4. Imaging ultrasonic probe beams in Solids;Wyatt;British Journal of NDT,1975
5. Baborovsky, V.M., Marsh, D.M. A schlieren study of ultrasonic pulse propagation and reflection. Ultrasonics 1971 Conference papers 86–88.