@misc{indiciaeb7f8d56a706d,
  title = {Perturbed ladder operator method: An algebraic recursive solution of perturbed wave equations.},
  author = {N Bessis and G Bessis},
  year = {1990},
  doi = {10.1103/physreva.42.1096},
  url = {https://pubmed.ncbi.nlm.nih.gov/9904132/},
  note = {Source identifier: 9904132}
}