@article{ref1,
title="Incentive magnitude, task orientation, and persistence",
journal="Child development",
year="1964",
author="Nakamura, C. Y. and Lowenkron, B. Z.",
volume="35",
number="",
pages="611-621",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0009-3920",
doi="",
url="http://dx.doi.org/"
}