TY  - RPRT
TI  - Stain indices of twenty-one asphalts : first supplement to NBS Report no. 4732 report on the evaluation of twenty-one coating-grade roofing asphalts
AU  - Greenfeld, Sidney H
AU  - Ishihara, Shigeru
PY  - 1957
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS RPT 5224
DO  - 10.6028/NBS.RPT.5224
ER  -