@misc{indiciae0669b8c2874d,
  title = {Spectrographic analyses of insoluble-residue samples, Joplin 1 degree x 2 degrees Quadrangle, Missouri and Kansas; drill hole Nos. 134, 135, and 136},
  author = {J. H. Bullock and H. W. Folger},
  year = {1990},
  doi = {10.3133/ofr90223},
  url = {https://pubs.usgs.gov/publication/ofr90223},
  note = {Source identifier: ofr90223}
}