@article{ref1,
title="Perceptual exploration in twins",
journal="Journal of experimental child psychology",
year="1972",
author="Matheny, A. P.",
volume="14",
number="1",
pages="108-116",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0022-0965",
doi="",
url="http://dx.doi.org/"
}