@article{britt_tsynkov_turkel_2013, title={A High-Order Numerical Method for the Helmholtz Equation with Nonstandard Boundary Conditions}, volume={35}, ISSN={1064-8275 1095-7197}, url={http://dx.doi.org/10.1137/120902689}, DOI={10.1137/120902689}, number={5}, journal={SIAM Journal on Scientific Computing}, publisher={Society for Industrial & Applied Mathematics (SIAM)}, author={Britt, D. S. and Tsynkov, S. V. and Turkel, E.}, year={2013}, month={Jan}, pages={A2255–A2292} }
 @article{britt_tsynkov_turkel_2010, title={A Compact Fourth Order Scheme for the Helmholtz Equation in Polar Coordinates}, volume={45}, ISSN={0885-7474 1573-7691}, url={http://dx.doi.org/10.1007/s10915-010-9348-3}, DOI={10.1007/s10915-010-9348-3}, number={1-3}, journal={Journal of Scientific Computing}, publisher={Springer Science and Business Media LLC}, author={Britt, S. and Tsynkov, S. and Turkel, E.}, year={2010}, month={Jan}, pages={26–47} }