@misc{indiciae0e31c9cffb5b,
  title = {Testing proportionality in the proportional odds model fitted with GEE.},
  author = {T R Stiger and H X Barnhart and J M Williamson},
  year = {1999},
  doi = {10.1002/(sici)1097-0258(19990615)18:11<1419::aid-sim127>3.0.co;2-q},
  url = {https://pubmed.ncbi.nlm.nih.gov/10399205/},
  note = {Source identifier: 10399205}
}