@article{ref1,
title="Theoretical approaches to human error",
journal="Ergonomics",
year="1973",
author="Singleton, W. T.",
volume="16",
number="6",
pages="727-737",
abstract="<p>[Abstract unavailable]</p> <p>Language: en</p>",
language="en",
issn="0014-0139",
doi="",
url="http://dx.doi.org/"
}