@misc{indiciae28c017610d2d,
  title = {Preliminary structure map of the northern part of the Piceance Creek basin, Colorado, and preliminary isopach map of the interval between the B-groove and orange marker of the Green River Formation, northern part of the Piceance Creek basin, Colorado},
  author = {John R. Dyni},
  year = {1968},
  doi = {10.3133/ofr6892},
  url = {https://pubs.usgs.gov/publication/ofr6892},
  note = {Source identifier: ofr6892}
}