@misc{indiciaef637a69a7e60,
  title = {Geologic map of the Valley View quadrangle, Schuylkill and Northumberland Counties, Pennsylvania},
  author = {J. Peter Trexler and Gordon H. Wood},
  year = {1968},
  doi = {10.3133/gq699},
  url = {https://pubs.usgs.gov/publication/gq699},
  note = {Source identifier: gq699}
}