@misc{indiciaeadecb777e31c,
  title = {Palynologic and petrographic intervals in the upper Pennsylvanian McLeansboro Group, Western Kentucky},
  author = {J.C. Hower and C.T. Helfrich and D.A. Williams},
  year = {1994},
  doi = {10.1016/0166-5162(94)90035-3},
  url = {https://pubs.usgs.gov/publication/70017671},
  note = {Source identifier: 70017671}
}