@article{ref1,
title="Perception of the horizontal or vertical with head upright, on the side, and inverted under static conditions, and during exposure to centripetal force",
journal="Aerospace medicine",
year="1962",
author="Graybiel, A. and Clark, B.",
volume="33",
number="",
pages="147-155",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0001-9402",
doi="",
url="http://dx.doi.org/"
}