TY  - RPRT
TI  - DETERMINATION OF MODE OF OCCURRENCE OF TRACE ELEMENTS IN THE UPPER FREEPORT COAL BED USING SIZE AND DENSITY SEPARATION PROCEDURES.
AU  - C.A. Palmer
AU  - R.H. Filby
PY  - 1983
UR  - https://pubs.usgs.gov/publication/70012053
ID  - 70012053
ER  -