@misc{horstmann_the_use_1993, 
author={Horstmann, M.,Gregory, J. K.,Schwalbe, K.-H.},
title={The use of the AC potential drop method for measuring the growth of surface cracks during fatigue},
year={1993},
howpublished = {journal article,GKSS report},
note = {Online available at: \url{} (DOI). Horstmann, M.; Gregory, J.; Schwalbe, K.: The use of the AC potential drop method for measuring the growth of surface cracks during fatigue. Materialpruefung. 1993. vol. 35, no. 78, 212-217.}}