M.G. Silk, B.H. Lidington (1975). "The potential of scattered or diffracted ultrasound in the determination of crack depth". Non-Destructive Testing. 8 (3): 146–151. doi:10.1016/0029-1021(75)90024-9. ISSN0029-1021.
Bray, Don (2003). "Ultrasonic Systems for Industrial Nondestructive Evaluation". Ultrasonic Nondestructive Evaluation Engineering and Biological Material Characterization. doi:10.1201/9780203501962.ch3 (inactive 12 November 2024). ISBN978-0-8493-1462-9.{{cite book}}: CS1 maint: DOI inactive as of November 2024 (link)
M.G. Silk, B.H. Lidington (1975). "The potential of scattered or diffracted ultrasound in the determination of crack depth". Non-Destructive Testing. 8 (3): 146–151. doi:10.1016/0029-1021(75)90024-9. ISSN0029-1021.