@misc{indiciae0050ac4d51d6,
  title = {Coal movement by railroads, 1974},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1977},
  doi = {10.3133/32526},
  url = {https://pubs.usgs.gov/publication/32526},
  note = {Source identifier: 32526}
}