@article{ref1,
title="An intercultural study of aggressive behavior on children's playgrounds",
journal="American journal of orthopsychiatry",
year="1974",
author="Bellak, L. and Antell, M.",
volume="44",
number="4",
pages="503-511",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0002-9432",
doi="",
url="http://dx.doi.org/"
}