@article{ref1,
title="The acoustical attenuation of some combinations of earplugs and earmuffs",
journal="Annals of occupational hygiene",
year="1987",
author="Rawlinson, R. D. and Wheeler, P. D. and Custard, G.",
volume="31",
number="3",
pages="299-309",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0003-4878",
doi="",
url="http://dx.doi.org/"
}