@misc{indiciae80caa60fe09d,
  title = {Effective summation over intermediate states in double-beta decay.},
  author = {J Engel and WC Haxton and P Vogel},
  year = {1992},
  doi = {10.1103/physrevc.46.r2153},
  url = {https://pubmed.ncbi.nlm.nih.gov/9968406/},
  note = {Source identifier: 9968406}
}