@misc{tzschichholz_beam_model_1994, 
author={Tzschichholz, F.,Herrmann, H. J.,Roman, H. E.,Pfuff, M.},
title={Beam model for hydraulic fracturing},
year={1994},
howpublished = {journal article},
note = {Online available at: \url{} (DOI). Tzschichholz, F.; Herrmann, H.; Roman, H.; Pfuff, M.: Beam model for hydraulic fracturing. Physical Review  B. 1994. vol. 49, no. 10, 7056-7059.}}