@article{ref1,
title="Aircraft noise-sound reduction techniques",
journal="Aviation, space, and environmental medicine",
year="1976",
author="Barriage, J. B.",
volume="47",
number="1",
pages="55-59",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0095-6562",
doi="",
url="http://dx.doi.org/"
}