@misc{indiciae9a4861cb11df,
  title = {An in situ occurrence of coal balls in the Amburgy coal bed, Pikeville Formation (Duckmantian), central Appalachian Basin, USA},
  author = {Stephen F. Greb and Cortland F. Eble and D.R. Chesnut and T.L. Phillips and James C. Hower},
  year = {1999},
  doi = {10.2307/3515395},
  url = {https://pubs.usgs.gov/publication/70021282},
  note = {Source identifier: 70021282}
}