@misc{indiciae8b3e25eb1a9b,
  title = {The geometric transfer function for cone and fan beam collimators.},
  author = {B M Tsui and G T Gullberg},
  year = {1990},
  doi = {10.1088/0031-9155/35/1/008},
  url = {https://pubmed.ncbi.nlm.nih.gov/2304971/},
  note = {Source identifier: 2304971}
}