@article{Spencer2006,
author = {Spencer, N. },
title= {Explaining the social gradient in smoking in pregnancy: Early life course accumulation and cross-sectional clustering of social risk exposures in the 1958 British national cohort},
year = {2006},
doi = {10.1016/j.socscimed.2005.07.026},
journal = {Social Science and Medicine },
volume = {62},
number = {5},
pages = {1250--1259},
}