@misc{Kleefeld2013, author = {Andreas Kleefeld}, title = {The exterior problem for the Helmholtz equation with mixed boundary conditions in three dimensions}, booktitle = {International Journal of Computer Mathematics}, volume = {89}, number = {17}, issn = {0020-7160}, doi = {10.1080/00207160.2012.709932}, url = {http://www.tandfonline.com/doi/full/10.1080/00207160.2012.709932}, institution = {FG Numerische Mathematik und Wissenschaftliches Rechnen}, type = {articler}, pages = {2392 -- 2409}, year = {2013}, }