1. Colla C. Advanced impact–echo technique for NDE of post-tensioned concrete highway infrastructure, Proceedings of the first international conference on Bridge Maintenance, Safety and Management, IABMAS’ 02, Barcelona, Spain; 14–17 July 2002. p. 8.
2. Jackson MJ, Tweeton DR. MIGRATOM-geophysical tomography using wavefront migration and fuzzy constraints, Report of Investigations 9497, US Dept. of The Interior, Bureau of Mines; 1994. ISBN: 1066-5552.
3. Ultrasonic tomographic impact–echo NDT of grouted duct P-T R.C. beams;Martin,2001
4. Accuracy of NDE in bridge assessment;Martin;Eng Struct,1998
5. Stack imagining of spectral amplitudes based on impact–echo for flaw detection;Ohtsu;NDT & E Int,2002