@misc{indiciaef785d91c5e72,
  title = {Method for insuring parallelism of implants placed simultaneously with maxillary sinus bone grafts.},
  author = {M S Block and J S Widner},
  year = {1991},
  doi = {10.1016/0278-2391(91)90389-4},
  url = {https://pubmed.ncbi.nlm.nih.gov/1848613/},
  note = {Source identifier: 1848613}
}