@article{ref1,
title="Aviation noise--evaluation and possibilities of its elimination",
journal="Zeitschrift fur die Gesamte Hygiene und Ihre Grenzgebiete",
year="1969",
author="Hilscher, J.",
volume="15",
number="9",
pages="670-673",
abstract="<p>[Abstract unavailable]</p><p>Language: de</p>",
language="de",
issn="0049-8610",
doi="",
url="http://dx.doi.org/"
}