BibTex format
@article{Feliu:2019:10.1183/13993003.00596-2019,
author = {Feliu, A and Fernandez, E and Martinez, C and Filippidis, FT},
doi = {10.1183/13993003.00596-2019},
journal = {Eur Respir J},
title = {Are smokers "hardening" or rather "softening"? An ecological and multilevel analysis across 28 European Union countries.},
url = {http://dx.doi.org/10.1183/13993003.00596-2019},
volume = {54},
year = {2019}
}