@misc{indiciae7e8dedabaafd,
  title = {Nonorthogonal natural orbitals from open-shell configuration-interaction calculations.},
  author = {Heaton, M. and Weltin, E.},
  year = {1969},
  url = {https://ntrs.nasa.gov/citations/19690064217},
  note = {Source identifier: 19690064217}
}