@article{ref1,
title="Commentary on Cannabis and Crash Risk: Concentration Effect Relation",
journal="Transportation research circular",
year="2006",
author="Ramaekers, Johannes Gerardus",
volume="",
number="E-C096",
pages="65-66",
abstract="These comments address the following: the role of tetrahydrocannabinol (THC) in driver impairment; contrasts between the results of epidemiological and experimental studies of THC; the role of higher doses and recent or past use of THC; threshold levels for THC; and the combined use of alcohol and THC.  Keywords: Cannabis impaired driving; Ethanol impaired driving <p />",
language="en",
issn="0097-8515",
doi="",
url="http://dx.doi.org/"
}