@article{ref1,
title="Classification of fractures of the middle of the face",
journal="Deutsche Stomatologie (1951)",
year="1971",
author="Pfeifer, H.",
volume="21",
number="7",
pages="569-571",
abstract="<p>[Abstract unavailable]</p><p>Language: de</p>",
language="de",
issn="0012-0790",
doi="",
url="http://dx.doi.org/"
}