@misc{indiciaebe4a03d08e29,
  title = {Sources of fertilizer minerals in South America; a preliminary study},
  author = {James Foster Harrington and Dwight Edward Ward and V.E. McKelvey},
  year = {1966},
  doi = {10.3133/b1240},
  url = {https://pubs.usgs.gov/publication/b1240},
  note = {Source identifier: b1240}
}