@misc{indiciae147f47817f94,
  title = {Methane, carbon dioxide, oxygen, and nitrogen in soil gas overlying coal beds of the Upper Cretaceous Fruitland Formation in the San Juan Basin, La Plata County, southwestern Colorado},
  author = {J. R. Herring and J.S. Ciener and J.M. Been and S.L. Szrzi and G.M. Reimer and D. D. Rice and B.C. Boyce},
  year = {1994},
  doi = {10.3133/ofr94295},
  url = {https://pubs.usgs.gov/publication/ofr94295},
  note = {Source identifier: ofr94295}
}