@article{ref1,
title="Eyestrain in VDU users: physical correlates and long-term effects",
journal="Human factors",
year="1983",
author="De Groot, J. P. and Kamphuis, A.",
volume="25",
number="4",
pages="409-413",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0018-7208",
doi="",
url="http://dx.doi.org/"
}