@article{ref1,
title="Sleep patterns in a lone global pilot",
journal="Aerospace medicine",
year="1973",
author="Preston, F. S. and Cussen, D. J.",
volume="44",
number="6",
pages="669-674",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0001-9402",
doi="",
url="http://dx.doi.org/"
}