@misc{indiciae3d705783046b,
  title = {Phase integral theory, coupled wave equations, and mode conversion.},
  author = {Robert G. Littlejohn and William G. Flynn},
  year = {1992},
  doi = {10.1063/1.165918},
  url = {https://pubmed.ncbi.nlm.nih.gov/12779962/},
  note = {Source identifier: 12779962}
}