A design for a yoke to detect a notch on edge by using magnetic flux leakage method H. Heidary, M. A. Mehrpouya, A. Ghalee and A. R. Oskouei Eur. Phys. J. Plus, 136 4 (2021) 368 Published online: 08 April 2021 DOI: 10.1140/epjp/s13360-021-01364-5