@article{ref1,
title="The absence of evidence is not the same as evidence for absence!",
journal="Addiction",
year="2008",
author="Bramness, Jørgen G. and Skurtveit, Svetlana and Gustavsen, Ingebjørg and Mørland, Jørg",
volume="103",
number="3",
pages="513-514",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0965-2140",
doi="10.1111/j.1360-0443.2007.02103.x",
url="http://dx.doi.org/10.1111/j.1360-0443.2007.02103.x"
}