Magnetic leakage fields calculated by the method of finite differences

Lord, 1977, Defect characterization from magnetic leakage fields', Brit J NDT, 14 Dobmann, 1982, New set-ups for mathematical-numerial solutions of magnetic leakage-flux testing with d.c. and a.c. mode in the FRG Förster, 1984, Neue Erkenntnisse auf dem Gebiet der zerstörungsfreien Prüfung mit magnetischem Streufluss, 287 Binns, K.J. and Lawrenson, P.J. 'Analysis and computation of electric and magnetic field problems, Pergamon Press, Oxford