Abdel-Magied, Rasha A., et al. “Serum Interleukin-6 in Systemic Sclerosis and Its Correlation With Disease Parameters and Cardiopulmonary Involvement”. Sarcoidosis, Vasculitis and Diffuse Lung Diseases, vol. 33, no. 4, Dec. 2016, pp. 321-30, https://mattioli1885journals.com/index.php/sarcoidosis/article/view/5170.