@article{ref1,
title="College students and alcohol, marijuana and tobacco: a comparison survey between 1967 and 1978",
journal="Journal of psychedelic drugs",
year="1979",
author="Silvestro, J. R. and Vacc, N. A.",
volume="11",
number="4",
pages="351-353",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0022-393X",
doi="",
url="http://dx.doi.org/"
}