1. Babuska, I., Ihlenburg, F., Paik, E.T., Sauter, S.A.: A generalized finite element method for solving the Helmholtz equation in two dimensions with minimal pollution, Comput. Meths. Appl. Mech. Eng., to appear
2. Babuska, I.; Sauter, S.: Is the pollution effect of the FEM avoidable for the Helmholtz equation considering high wave numbers, Technical Note BN-1172 (1994), IPST, U of Maryland at College Park
3. Bayliss, A.; Goldstein, C.I.; Turkel, E.: On accuracy conditions for the numerical computation of wares, J. Comp. Phys. 59 (1985), 396–404
4. Burnett, D.S., 4 three-dimensional acoustic infinite element based on a prolate spheroidal multipole expansion, J. Acoust. Soc. Am. 96 (1994), 5, 2798–2816
5. L. Demkowicz, Asymptotic convergence in finite and boundary element methods: part I: theoretical results, Computers Math. Applic. 27, 12, 69–84 (1994)