TY - GEN AU - Grace Hahm AU - Michael Nelson AU - Johanna Camara AU - Blaza Toman C2 - Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD DA - 2021-09-02 04:09:00 DO - https://doi.org/10.6028/NIST.SP.260-210 LA - en PB - Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD PY - 2021 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) UR - https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=932138 ER -