@misc{indiciae6c73d7ee7afb,
  title = {Distribution of thorium, uranium, and potassium in igneous rocks of the Boulder batholith region, Montana, and its bearing on radiogenic heat production and heat flow},
  author = {R.I. Tilling and David Gottfried},
  year = {1969},
  doi = {10.3133/pp614e},
  url = {https://pubs.usgs.gov/publication/pp614E},
  note = {Source identifier: pp614E}
}