@misc{indiciaeb983635bd593,
  title = {A finite element conjugate gradient FFT method for scattering},
  author = {Collins, Jeffery D. and Zapp, John and Hsa, Chang-Yu and Volakis, John L.},
  year = {1990},
  url = {https://ntrs.nasa.gov/citations/19910005163},
  note = {Source identifier: 19910005163}
}