1. Crack Propagation in Thin Metal Sheet Under Repeated Loading;Liu;A.S.M.E.,1961
2. Electric Potential Technique for Determining Crack Growth;Anctil;Proc. ASTM.,1963
3. 3. H. H. Johnson : “Calibrating the Electric Potential Method for Studying Slow Crack Growth”. Materials Research and Standards, Sept., 1965.
4. Calibration of the Electric Resistance Method of Studying Crack Propagation;Johnson;Cornell Univ. Tech. Memo.,1962
5. 5. J. E. Srawley and W. F. Brown : “Plane Strain Crack Toughness Testing”. ASTM, STP 410.