@misc{indiciaec2935fa6ce2a,
  title = {40Ar/39Ar ages of some Challis Volcanic Group rocks and the initiation of Tertiary sedimentary basins in southwestern Montana},
  author = {John W. M’Gonigle and G. Brent Dalrymple},
  year = {1996},
  doi = {10.3133/b2132},
  url = {https://pubs.usgs.gov/publication/b2132},
  note = {Source identifier: b2132}
}