@misc{indiciae3ab6429c5697,
  title = {Geologic map of the Yarumal Quadrangle (H-8) and part of the Ituango Quadrangle (H-7), Colombia},
  author = {Alvarez A. Jairo and Rico H. Hector and Hernan Vasquez},
  year = {1975},
  doi = {10.3133/i842},
  url = {https://pubs.usgs.gov/publication/i842},
  note = {Source identifier: i842}
}