@inproceedings{hengst_methods_2009,
 author = {Hengst, K. and Drotleff, H. and Wack, R. and Blau, M.},
 title = {Methods to characterize the acoustic properties of periodic surfaces},
 booktitle = {Proceedings of NAG/DAGA 2009, Rotterdam (The Netherlands)},
 year = {2009},
}