@misc{indiciaef0d04a0317ac,
  title = {Gravitational spreading of steep-sided ridges ("sackung") in Colorado},
  author = {Dorothy H. Radbruch-Hall and David J. Barnes and Roger B. Colton},
  year = {1977},
  url = {https://pubs.usgs.gov/publication/70233534},
  note = {Source identifier: 70233534}
}