@misc{indiciae4a12c20724c3,
  title = {Spectral multigrid methods for elliptic equations 2},
  author = {Zang, T. A. and Wong, Y. S. and Hussaini, M. Y.},
  year = {1983},
  url = {https://ntrs.nasa.gov/citations/19830020666},
  note = {Source identifier: 19830020666}
}