@article{ref1,
title="Outerdirectedness and the puzzle performance of nonretarded and retarded children",
journal="American journal of mental deficiency",
year="1972",
author="Drotar, Dennis",
volume="77",
number="2",
pages="230-236",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0002-9351",
doi="",
url="http://dx.doi.org/"
}