TY  - RPRT
TI  - The occurrence of minor elements in ash of low-rank coal from Texas, Colorado, North Dakota, and South Dakota
AU  - Maurice Deul
AU  - C. S. Annell
PY  - 1956
DO  - 10.3133/b1036h
UR  - https://pubs.usgs.gov/publication/b1036H
ID  - b1036H
ER  -