1. Sperry Rail Service. Rail Defect Manual, 1989.
2. Improved ultrasonic testing of railroad rail for transverse discontinuities in the rail head using higher order Rayleigh (M21) waves;Grewal;Mater Evaluat,1996
3. Rail-flaw detection picks up the pace;Tuzik;Railway Track Struct,1995
4. History and development of rail flaw detector cars;Keevil;Mater Evaluat,1991
5. Fishing for fissures: sources for the history of rail testing cars, 1927–1960;Wickre;Mater Evaluat,1985