@article{ref1,
title="The analysis of cardiac interbeat interval sequences and the effects of mental work load",
journal="Proceedings of the Royal Society of Medicine",
year="1971",
author="Sayers, B. M.",
volume="64",
number="7",
pages="707-710",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0035-9157",
doi="",
url="http://dx.doi.org/"
}