TY  - RPRT
TI  - Supplement to National Bureau of Standards Circular 398: standard samples issued or in preparation by the National Bureau of Standards
PY  - 1940
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS CIRC 398sup1940
DO  - 10.6028/NBS.CIRC.398sup1940
ER  -