TY  - RPRT
TI  - Certification of Standard Reference Materials 2969 and 2970 : vitamin D metabolites in frozen human serum (total 25-hydroxyvitamin D low level) and (25-hydroxyvitamin D2 high level)
AU  - Hahm, Grace
AU  - Nelson, Michael
AU  - Camara, Johanna
AU  - Toman, Blaza
PY  - 2021
PB  - National Institute of Standards and Technology (U.S.)
CY  - Gaithersburg, MD
SN  - NIST SP 260-210
DO  - 10.6028/NIST.SP.260-210
ER  -