@article{ref1,
title="Preferred declination of the line of sight",
journal="Human factors",
year="1986",
author="Kroemer, K. H. and Hill, S. G.",
volume="28",
number="2",
pages="127-134",
abstract="Abstract unavailable.",
language="",
issn="0018-7208",
doi="",
url="http://dx.doi.org/"
}