TY  - RPRT
TI  - Use of altered volcanic ash falls in stratigraphic studies of coal-bearing sequences: an example from the Upper Cretaceous Ferron Sandstone Member of the Mancos Shale in central Utah.
AU  - Thomas A. Ryer
AU  - R.E. Phillips
AU  - B.F. Bohor
AU  - R. M. Pollastro
PY  - 1980
DO  - 10.1130/0016-7606(1980)91<579:uoavaf>2.0.co;2
UR  - https://pubs.usgs.gov/publication/70012353
ID  - 70012353
ER  -