TY  - RPRT
TI  - Natural gamma aeroradioactivity map of the Pittsburgh area, Pennsylvania, Ohio, West Virginia, and Maryland
AU  - R. G. Bates
PY  - 1966
DO  - 10.3133/gp555
UR  - https://pubs.usgs.gov/publication/gp555
ID  - gp555
ER  -