@misc{indiciaeaac73750266d,
  title = {Integrability and action operators in quantum Hamiltonian systems.},
  author = {V V Stepanov and G Müller},
  year = {2001},
  doi = {10.1103/physreve.63.056202},
  url = {https://pubmed.ncbi.nlm.nih.gov/11414985/},
  note = {Source identifier: 11414985}
}