@misc{indiciaedffcacf8f599,
  title = {[Opacity and opacity changes in composites].},
  author = {T Luckenbach and G M Lösche and J F Roulet},
  year = {1991},
  url = {https://pubmed.ncbi.nlm.nih.gov/1817946/},
  note = {Source identifier: 1817946}
}