@misc{indiciae6422bea979b2,
  title = {Geochemical mapping of the Denver, Colorado (USA) urban area: A comparison of studies in 1972 and 2005},
  author = {D. B. Smith and R. G. Garrett and G. Closs and K.J. Ellefsen and J.E. Kilburn and J.D. Horton and S. M. Smith},
  year = {2011},
  url = {https://pubs.usgs.gov/publication/70004427},
  note = {Source identifier: 70004427}
}