Bedner, M.
, Lippa, K.
and Tai, S.
(2013),
Results from the NIST/NIH Vitamin D Metabolites Quality Assurance Program: Five Years of Comparability Studies, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=917723
(Accessed November 17, 2025)