@misc{indiciae2e504d8c9336,
  title = {Geochemical studies of clay minerals III. The determination of free silica and free alumina in montmorillonites},
  author = {Margaret D. Foster},
  year = {1953},
  doi = {10.1016/0016-7037(53)90003-9},
  url = {https://pubs.usgs.gov/publication/70011109},
  note = {Source identifier: 70011109}
}