NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used.

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Vitamin D Home Page. About Vitamin D [40 paragraphs]. University of California, Riverside, Vitamin D Home Page [On-line information]. Available FTP: http://vitamind.ucr.edu/about.html

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DeLuca, H. [Reviewed] (2001 January 18, Updated). Vitamin D [35 paragraphs]. Linus Pauling Institute [On-line information]. Available FTP: http://www.orst.edu/dept/lpi/infocenter/vitamins/vitaminD/

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(November 2006) Quest Diagnostics, Vitamin D, 25-Hydroxy, Test Summary (online information). Available FTP: http://www.questdiagnostics.com/hcp/topics/endo/vitamin_d.html

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(November 2006) ARUP Laboratory, Vitamin D, 25-Hydroxy, Test Directory (online information). Available FTP: http://www.aruplab.com/guides/ug/tests/0070277.jsp

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Saenger AK, et al. Quantification of Serum 25-Hydroxyvitamin D2 and D3 Using HPLC-Tandem Mass Spectrometry and Examination of Reference Intervals for Diagnosis of Vitamin D Deficiency. American Journal of Clinical Pathology 2006;125:914-920.

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