Oncul, H., M. Fuat Alakus, M. Caglayan, F. Yilmaz Oncul, U. Dag, and E. Arac. “Impact of Vitamin D Supplementation on the Ocular Surface in Patients With Vitamin D Deficiency”. Annals of Medical Research, vol. 27, no. 10, May 2021, pp. 2726-30, http://www.annalsmedres.org/index.php/aomr/article/view/989.