title: A method for the determination of the circulating concentration of vitamin D.
authors.affiliation: Vitamin D, Skin, and Bone Research Laboratory, Boston University School of Medicine, Boston, MA 02118, USA.
authors.forename: T C
authors.initials: TC
authors.lastname: Chen
authors.forename: A K
authors.initials: AK
authors.lastname: Turner
authors.forename: M F
authors.initials: MF
authors.lastname: Holick