@misc{indiciaeb06367a87f89,
  title = {Available sand and gravel resources in southern New Hampshire},
  author = {Joseph S. Duval and David M. Sutphin and Herbert A. Pierce},
  year = {2003},
  doi = {10.3133/ofr03373},
  url = {https://pubs.usgs.gov/publication/ofr03373},
  note = {Source identifier: ofr03373}
}