@article{ref1,
title="Cockpit noise intensity: fifteen single-engine light aircraft. AM 68-21",
journal="AM reports",
year="1968",
author="Tobias, J. V.",
volume="",
number="",
pages="1-6",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="1545-1518",
doi="",
url="http://dx.doi.org/"
}