@article{ref1,
title="Mode of spending free time among Warsaw children 9- to 13-years-old",
journal="Roczniki Panstwowego Zakladu Higieny",
year="1981",
author="Goryński, P. and Polus-Szeniawska, E.",
volume="32",
number="5-6",
pages="485-492",
abstract="<p>[Abstract unavailable]</p><p>Language: pl</p>",
language="pl",
issn="0035-7715",
doi="",
url="http://dx.doi.org/"
}