Sapiejka, Ewa, et al. “The Evaluation of α-Tocopherol Concentration Instead of α-tocopherol:Cholesterol Ratio in Adult Cystic Fibrosis Patients Results in the Overestimation of Vitamin E Deficiency”. Journal of Medical Science, vol. 88, no. 1, Mar. 2019, pp. 21-25, https://doi.org/10.20883/jms.313.