@misc{indiciae7ab588a8e13e,
  title = {A single variable variational approximation for a perturbed schrodinger equation.},
  author = {W B Brown and P R Certain},
  year = {1967},
  doi = {10.1073/pnas.57.5.1206},
  url = {https://pubmed.ncbi.nlm.nih.gov/16591557/},
  note = {Source identifier: 16591557}
}