Devices for detection of defects at early stages of their initiation at determination of technical condition of mechanisms - R. M. Yuzefovych; I. M. Yavorskyi; I. Y. Matsko; O. V. Lychak; H. R. Trokhym; Yu. Dzeryn; I. H. Stetsko (Technical diagnostics and non-destructive testing, 2020)