@article{ref1,
title="Communication and sound transmission in helium and various gases at reduced pressures",
journal="Aerospace medicine",
year="1964",
author="Cooke, J. P.",
volume="35",
number="",
pages="1050-1053",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0001-9402",
doi="",
url="http://dx.doi.org/"
}