@article{ref1,
title="The dark focus of the human eye and its relationship to age and visual defect",
journal="Human factors",
year="1983",
author="Simonelli, N. M.",
volume="25",
number="1",
pages="85-92",
abstract="Abstract unavailable.",
language="",
issn="0018-7208",
doi="",
url="http://dx.doi.org/"
}