@article{ref1,
title="Sleep and its pharmacologic treatment",
journal="Landarzt",
year="1967",
author="Niehues, H.",
volume="43",
number="13",
pages="599-604",
abstract="<p>[Abstract unavailable]</p><p>Language: de</p>",
language="de",
issn="0023-7728",
doi="",
url="http://dx.doi.org/"
}