@unpublished{Altonji2013,
author = {Joseph Altonji and Sarah Cattan and Iain Ware},
title = {Identifying sibling influence on teenage substance use},
year = {2013},
month = {Mar},
doi = {10.1920/wp/ifs/2013.1304},
url = {http://www.ifs.org.uk/wps/wp1304.pdf},
}