@article{ref1,
title="On the psychological reality of cognitive structures: a tentative synthesis of Piaget's and Bruner's theories",
journal="Child development",
year="1974",
author="Steiner, G.",
volume="45",
number="4",
pages="891-899",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0009-3920",
doi="",
url="http://dx.doi.org/"
}