@misc{indiciaedce073aeddcf,
  title = {Contributions to economic geology, 1906, Part I, Metals and nonmetals except fuels--Introduction; gold and silver},
  author = {C. W. Hayes and William Harvey Emmons and Edwin Clarence Eckel and Lester H. Woolsey and Arthur James Collier and Alfred Reginald Schultz},
  year = {1907},
  doi = {10.3133/b315a},
  url = {https://pubs.usgs.gov/publication/b315A},
  note = {Source identifier: b315A}
}