@misc{heerens_determination_of_2006, 
author={Heerens, J., Schoedel, M., Schwalbe, K.-H.},
title={Determination of critical crack tip opening angle using the CTOD measurement technique},
year={2006},
howpublished = {conference lecture: Geesthacht (D);},
note = {Heerens, J.; Schoedel, M.; Schwalbe, K.: Determination of critical crack tip opening angle using the CTOD measurement technique. Integrity of light-weight thin-walled structures, International Workshop. Geesthacht (D), 2006.}}