00517naa#a2200157#i#450# EN\\bibl\39640 20240501184907.3 1609-3178 20201002b2020####ek#y0engy0150####ca RU Sensitivity and Amplitude Measured Characteristics of the Defect. Review of Changes in Rail Flaw Detection over a Quarter Century Journal article Saint-Petersburg LLC SVEN 2020 11 с. Journal article local Molotkov Sergey L. naukaru.ru