Hagmeyer, Lars, et al. “Validation of Transbronchial Cryobiopsy in Interstitial Lung Disease - Interim Analysis of a Prospective Trial and Critical Review of the Literature”. Sarcoidosis, Vasculitis and Diffuse Lung Diseases, vol. 33, no. 1, Mar. 2016, pp. 2-9, https://mail.mattioli1885journals.com/index.php/sarcoidosis/article/view/4345.