Bender, David A.; Mayes, Peter A (2006). "Micronutrients: Vitamins & Minerals". Dalam Victor W. Rodwell; Murray, Robert F.; Harper, Harold W.; Granner, Darryl K.; Mayes, Peter A. Harper's Illustrated Biochemistry. New York: Lange/McGraw-Hill. hlm. 492–3. ISBN0-07-146197-3.Pemeliharaan CS1: Menggunakan parameter penyunting (link) Diakses 10 Desember 2008 melalui Google Book Search.
doi.org
Holick, MF; Deluca, HF; Avioli, LV (1972). "Isolation and identification of 25-hydroxycholecalciferol from human plasma". Archives of Internal Medicine. 129 (1): 56–61. doi:10.1001/archinte.1972.00320010060005. PMID4332591.
Holick, MF; Deluca, HF; Avioli, LV (1972). "Isolation and identification of 25-hydroxycholecalciferol from human plasma". Archives of Internal Medicine. 129 (1): 56–61. doi:10.1001/archinte.1972.00320010060005. PMID4332591.