@misc{indiciaeb9845c57afa7,
  title = {Coal fields of Punjab and North-West Frontier Provinces, and Azad Kashmir, Pakistan},
  author = {Peter D. Warwick and Farhat Husain},
  year = {1990},
  url = {https://pubs.usgs.gov/publication/70195528},
  note = {Source identifier: 70195528}
}