@article{ref1,
title="Aircraft Maintenance Costs and Aircraft Age",
journal="Transportation quarterly",
year="1994",
author="Dumville, JC and Quinn, TJ",
volume="48",
number="1",
pages="55-63",
abstract="<p>[Abstract unavailable]</p>",
language="",
issn="0278-9434",
doi="",
url="http://dx.doi.org/"
}