@misc{indiciaec78de65c8828,
  title = {A case-control study of multiple sclerosis.},
  author = {E A Operskalski and B R Visscher and R M Malmgren and R Detels},
  year = {1989},
  doi = {10.1212/wnl.39.6.825},
  url = {https://pubmed.ncbi.nlm.nih.gov/2725877/},
  note = {Source identifier: 2725877}
}