@article{ref1,
title="The influence of small doses of carbon monoxide upon heart rate",
journal="Respiration: international review of thoracic diseases",
year="1972",
author="Shephard, R. J.",
volume="29",
number="5",
pages="516-521",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0025-7931",
doi="",
url="http://dx.doi.org/"
}