@article{Doll2004,
author = {Doll, R. and Peto, R. and Boreham, J. and Sutherland, I.},
title= {Mortality in relation to smoking: 50 years' observations on male British doctors},
year = {2004},
journal = {BMJ},
volume = {328},
number = {7455},
pages = {1519},
}