@misc{indiciaea91fcb694632,
  title = {In situ analysis of coal using a 252CF-Ge(Li) borehole sonde},
  author = {F. E. Senftle and A. B. Tanner and P. W. Philbin and G. R. Boynton and C. W. Schram},
  year = {1978},
  url = {https://pubs.usgs.gov/publication/70047767},
  note = {Source identifier: 70047767}
}