@misc{indiciae9a71af5651e1,
  title = {Loop vs. shield: a competing risks analysis of IUD termination.},
  author = {J Herson and C L Crocker and E Butts},
  year = {1976},
  doi = {10.1016/s0010-7824(76)80009-1},
  url = {https://pubmed.ncbi.nlm.nih.gov/975812/},
  note = {Source identifier: 975812}
}