@misc{indiciae2542431e8172,
  title = {Methadone dose and urine morphine.},
  author = {J F Maddux and M Esquivel and K N Vogtsberger and D P Desmond},
  year = {1991},
  doi = {10.1016/0740-5472(91)90039-d},
  url = {https://pubmed.ncbi.nlm.nih.gov/1664864/},
  note = {Source identifier: 1664864}
}