@misc{indiciae58a804bcb76f,
  title = {A possible petroleum related helium anomaly in the soil gas, Boulder and Weld Counties, Colorado},
  author = {Alan A. Roberts and M.C. Dalziel and L.A. Pogorski and S.G. Quirt},
  year = {1976},
  doi = {10.3133/ofr76544},
  url = {https://pubs.usgs.gov/publication/ofr76544},
  note = {Source identifier: ofr76544}
}