@misc{indiciaeffa84759f9d3,
  title = {Interfacing U.S. census map files with statistical graphics software: application and use in epidemiology.},
  author = {M Rizzardi and M S Mohr and D W Merrill and S Selvin},
  year = {1993},
  doi = {10.1002/sim.4780121919},
  url = {https://pubmed.ncbi.nlm.nih.gov/8272673/},
  note = {Source identifier: 8272673}
}