@misc{indiciae71e60920ddd5,
  title = {Distribution and abundance of gold and other selected elements in altered bedrock, Empire Mining district, Clear Creek County, Colorado},
  author = {Maurice A. Chaffee},
  year = {1972},
  doi = {10.3133/b1278c},
  url = {https://pubs.usgs.gov/publication/b1278C},
  note = {Source identifier: b1278C}
}