@article{ref1,
title="Survey of adolescent drug use. I. Sex and grade distribution",
journal="American journal of public health",
year="1971",
author="Johnson, K. G. and Donnelly, J. H. and Scheble, R. and Wine, R. L. and Weitman, M.",
volume="61",
number="12",
pages="2418-2432",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0090-0036",
doi="",
url="http://dx.doi.org/"
}