Samigullina, A A Microstructure changes in ultrafine-grained nickel processed by high pressure torsion under ultrasonic treatment. [electronic resource] - Ultrasonics 01 2018 - 313-321 p. digital Publication Type: Journal Article; Research Support, Non-U.S. Gov't ISSN: 1874-9968 Standard No.: 10.1016/j.ultras.2017.09.005 doi