Hanif, Muhammad, Shoaib, et al. “Video Assisted Thoracoscopic Surgery (VATS) Lung Biopsy for Non-Responsive Patients of Interstitial Lung Disease (ILD)”. Pakistan Armed Forces Medical Journal, vol. 61, no. 1, Mar. 2011, https://pafmj.org/PAFMJ/article/view/1837.