Młodożeniec, A., R. Orłowska-Florek, A. Czarnożycka-Wróbel, K. Gargasz, and A. Gala-Błądzińska. “Nonthyroidal illness syndrome as independent predictor of hospital mortality in the elderly hospitalized patients with COVID-19 pneumonia – single-center observation”. European Journal of Clinical and Experimental Medicine, vol. 20, no. 3, Sept. 2022, pp. 348–354, doi:10.15584/ejcem.2022.3.14.