@article{ref1,
title="Noise from aircraft at supersonic speeds",
journal="Nature",
year="1953",
author="Warren, C. H. E. and Bastin, E. W. and Rothwell, P.",
volume="171",
number="4344",
pages="214-216",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0028-0836",
doi="",
url="http://dx.doi.org/"
}