@misc{indiciae82de89259eef,
  title = {Composition and time relations of plutonic and associated volcanic rocks, Boulder Batholith Region, Montana},
  author = {Robert I. Tilling},
  year = {1974},
  doi = {10.1130/0016-7606(1974)85<1925:catrop>2.0.co;2},
  url = {https://pubs.usgs.gov/publication/70211011},
  note = {Source identifier: 70211011}
}