@misc{indiciaeac6f8e066c63,
  title = {Acoustic transmission in lined flow ducts - A finite element eigenvalue problem},
  author = {Astley, R. J. and Eversman, W.},
  year = {1981},
  url = {https://ntrs.nasa.gov/citations/19820034128},
  note = {Source identifier: 19820034128}
}