1. United States Patent: 6128081. “Method and System for Measuring a Physical Parameter of at Least One Layer of a Multilayer Article Without Damaging the Article and Sensor Head for Use Therein”, Perceptron, Inc. 2000.
2. K. PAIGE, “CPC-48-A—System for Noncontact Film Build Measuring in Production”, REVIEW OF PROGRESS IN QUANTITATIVE NDE, Bowdoin College, Brunswick, Maine, July 29–August 3, 2001
3. S. J. HARRIS, Private communication, “ATC-Sowerby” (BAE Systems: Bristol, UK.
4. D. P. ALMOND and P. M. PATEL, Photothermal Science and Techniques (Chapman and Hall: 1996).
5. DIN 50992-2: 2002–05, “Coating Thickness Measurements of Coatings and Characterisation of Surfaces with Surface Waves—Part 2: Thickness Measurement of Coatings by Photothermic Methods”.