TY  - RPRT
TI  - Evaluation of methods for the assay of radium-228 in water 
AU  - Noyce, J R
PY  - 1981
PB  - National Bureau of Standards
CY  - Gaithersburg, MD
SN  - NBS TN 1137
DO  - 10.6028/NBS.TN.1137
ER  -