@article{ref1,
title="Frequency of non-fatal heroin overdose: survey of heroin users recruited in non-clinical settings",
journal="British medical journal: BMJ",
year="1996",
author="Gossop, M. and Griffiths, P. and Powis, B. and Williamson, S. and Strang, J.",
volume="313",
number="7054",
pages="402-402",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0959-8138",
doi="",
url="http://dx.doi.org/"
}