@misc{13050,
  author = {Y. Tsompanopoulou and V. Dougalis and N. Kampanis and E. Vavalis},
  title = {A PDE-Level Iterative Method for the Numerical Solution of Helmholtz Equation in Underwater Acoustics},
  year = {1996},
  number = {TR-96-7},
  publisher = {Ins. Appl. Computational Math. Greece},
}