@misc{indiciaef490094bef69,
  title = {Altitude and configuration of the potentiometric surface in the crystalline and metasedimentary rocks, northeastern Chester County, Pennsylvania, May through October 1990},
  author = {B. Craig McManus},
  year = {1992},
  doi = {10.3133/wri914182},
  url = {https://pubs.usgs.gov/publication/wri914182},
  note = {Source identifier: wri914182}
}