@article{ref1,
title="Single and dual axis tracking as a function of system dynamics",
journal="Human factors",
year="1968",
author="Ziegler, P. N.",
volume="10",
number="3",
pages="273-276",
abstract="Abstract unavailable.",
language="",
issn="0018-7208",
doi="",
url="http://dx.doi.org/"
}