Biswas, Abhishek, and Michael P Donahoe. “The Many Faces of Pulmonary Langerhans Cell Histiocytosis”. Sarcoidosis, Vasculitis and Diffuse Lung Diseases, vol. 31, no. 3, Oct. 2014, pp. 244-8, https://mattioli1885journals.com/index.php/sarcoidosis/article/view/3308.