@article{ref1,
title="Learning to control heart rate: effects of varying incentive and criterion of success on task performance",
journal="Psychophysiology",
year="1976",
author="Lang, Peter J. and Twentyman, C. T.",
volume="13",
number="5",
pages="378-385",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0048-5772",
doi="",
url="http://dx.doi.org/"
}