BibTex format
@article{Al:2020:10.1136/tobaccocontrol-2018-054870,
author = {Al, Oweini D and Jawad, M and Akl, EA},
doi = {10.1136/tobaccocontrol-2018-054870},
journal = {TOBACCO CONTROL},
pages = {577--584},
title = {The association of waterpipe tobacco smoking with later initiation of cigarette smoking: a systematic review and meta-analysis exploring the gateway theory},
url = {http://dx.doi.org/10.1136/tobaccocontrol-2018-054870},
volume = {29},
year = {2020}
}