@article{ref1,
title="Home and recess physical activity of Hong Kong children",
journal="Research quarterly for exercise and sport",
year="1999",
author="Johns, D. P. and Ha, Amy S. C.",
volume="70",
number="3",
pages="319-323",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0270-1367",
doi="",
url="http://dx.doi.org/"
}