@misc{indiciaed245141ed55e,
  title = {Transparent blocks--an aid in simulation.},
  author = {D B Hughes and R Rodriguez},
  year = {1981},
  doi = {10.1016/0360-3016(81)90200-5},
  url = {https://pubmed.ncbi.nlm.nih.gov/7333915/},
  note = {Source identifier: 7333915}
}