@article{Berg2013,
author = {Berg, C.J. and Wen, H. and Cummings, J.R. and Ahluwalia, J.S. and Druss, B.G. },
title= {Depression and substance abuse and dependency in relation to current smoking status and frequency of smoking among nondaily and daily smokers},
year = {2013},
doi = {10.1111/j.1521-0391.2013.12041.x},
journal = {American Journal on Addictions },
volume = {22},
number = {6},
pages = {581--589},
}