@misc{indiciae882c714a0fb9,
  title = {Ovulation in relation to cervical canal diameter.},
  author = {L B Shettles},
  year = {1988},
  doi = {10.1016/0002-9378(88)90607-2},
  url = {https://pubmed.ncbi.nlm.nih.gov/3207142/},
  note = {Source identifier: 3207142}
}