BibTex format
@article{Charig:1991,
author = {Charig, MJ and Stutley, JE and Padley, SPG and Hansell, DM},
journal = {Clinical radiology},
title = {The value of negative needle biopsy in suspected operable lung cancer},
url = {http://www.sciencedirect.com/science/article/pii/S0009926005808566},
year = {1991}
}