Ford, Jennifer, Ana Hategan, James A. Bourgeois, Daniel K. Tisi, and Glen L. Xiong. “Hypovitaminosis D in Delirium: A Retrospective Cross-Sectional Study”. Canadian Geriatrics Journal 16, no. 4 (September 27, 2013): 186–191. Accessed August 8, 2022. https://cgjonline.ca/index.php/cgj/article/view/79.