@misc{indiciae8793bb2eb1ec, title = {Digital map of water levels in 1980 for the High Plains Aquifer in parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming}, author = {Joel R. Cederstrand and Mark F. Becker}, year = {1999}, doi = {10.3133/ofr99263}, url = {https://pubs.usgs.gov/publication/ofr99263}, note = {Source identifier: ofr99263} }