@article{ref1,
title="Exertion of forces by children performing a free-style jump",
journal="International journal for consumer and product safety",
year="1998",
author="Moes, C.c.m. and Visser, RJ and de Winter, P. E.",
volume="5",
number="4",
pages="215-224",
abstract="Abstract unavailable.<p />",
language="",
issn="1387-3059",
doi="",
url="http://dx.doi.org/"
}