@misc{indiciaee8e82ba9162b,
  title = {Spectrographic analyses of insoluble-residue samples Joplin 1 degree x 2 degrees Quadrangle, Missouri and Kansas; drill hole Nos. 112, 113, 114, and 115},
  author = {J. H. Bullock and H. W. Folger},
  year = {1990},
  doi = {10.3133/ofr906},
  url = {https://pubs.usgs.gov/publication/ofr906},
  note = {Source identifier: ofr906}
}