@misc{indiciae6c0d381d6ce8,
  title = {Survey of trace elements in coals and coal-related materials by neutron activation analysis},
  author = {R.R. Ruch and R.A. Cahill and J.K. Frost and L.R. Camp and H.J. Gluskoter},
  year = {1977},
  doi = {10.1007/bf02520217},
  url = {https://pubs.usgs.gov/publication/70000748},
  note = {Source identifier: 70000748}
}