@misc{indiciaea59e2e8a231f,
  title = {Interrelation between variational principles for scattering amplitudes and generalized R-matrix theory.},
  author = {CW McCurdy and TN Rescigno and BI Schneider},
  year = {1987},
  doi = {10.1103/physreva.36.2061},
  url = {https://pubmed.ncbi.nlm.nih.gov/9899096/},
  note = {Source identifier: 9899096}
}