Haroon, Ali, et al. “Frequency of Vitamin D Deficiency in Cirrhotic Versus Non-Cirrhotic Liver Disease Patients”. Journal of Liaquat University of Medical & Health Sciences, vol. 23, no. 03, Sept. 2024, pp. 238-43, http://ojs.lumhs.edu.pk/index.php/jlumhs/article/view/1331.