@article{ref1,
title="Note on measurement of visual after-image intensity as a function of time",
journal="Vision research",
year="1964",
author="Ekman, G. and Lindman, R.",
volume="4",
number="11",
pages="579-584",
abstract="<p>[Abstract unavailable]</p> <p>Language: en</p>",
language="en",
issn="0042-6989",
doi="",
url="http://dx.doi.org/"
}