APA-viite (7. p.)

Avenell, A., Cook, J., Maclennan, G., & Macpherson, G. (2007). Vitamin D supplementation to prevent infections: A sub-study of a randomised placebo-controlled trial in older people (RECORD trial, ISRCTN 51647438).

Chicago-viite (17. p.)

Avenell, A., J. Cook, G. Maclennan, ja G. Macpherson. Vitamin D Supplementation to Prevent Infections: A Sub-study of a Randomised Placebo-controlled Trial in Older People (RECORD Trial, ISRCTN 51647438). 2007.

MLA-viite (9. p.)

Avenell, A., et al. Vitamin D Supplementation to Prevent Infections: A Sub-study of a Randomised Placebo-controlled Trial in Older People (RECORD Trial, ISRCTN 51647438). 2007.

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