@misc{indiciaeaff992ca58f2,
  title = {Hillside materials and slopes of the San Francisco Bay region, California},
  author = {S. D. Ellen and C. M. Wentworth},
  year = {1995},
  doi = {10.3133/pp1357},
  url = {https://pubs.usgs.gov/publication/pp1357},
  note = {Source identifier: pp1357}
}