@misc{zerbst_fracture_mechanics_2008, 
author={Zerbst, U.},
title={Fracture Mechanics in Railway Application},
year={2008},
howpublished = {conference lecture: Porto (P); 07.-09.07.2008},
note = {Online available at: \url{} (DOI). Zerbst, U.: Fracture Mechanics in Railway Application. Conference on Engineering Problems of Railways. Porto (P), 2008.}}