TY  - RPRT
TI  - The chromograph, a new analytical tool for laboratory and field use
AU  - Rollin Elbert Stevens
AU  - Hubert William Lakin
PY  - 1949
DO  - 10.3133/cir63
UR  - https://pubs.usgs.gov/publication/cir63
ID  - cir63
ER  -