@misc{indiciae61149f9bf5a7,
  title = {Correlation energy of two-electron systems},
  author = {Konowalow, D. D. and Rosenfeld, J. L. J.},
  year = {1964},
  url = {https://ntrs.nasa.gov/citations/19650025709},
  note = {Source identifier: 19650025709}
}