@article{ref1,
title="The prevalence of injured anterior teeth in English schoolchildren and adults",
journal="Journal of the International Association of Dentistry for Children",
year="1973",
author="Clarkson, B. H. and Longhurst, P. and Sheiham, A.",
volume="4",
number="1",
pages="21-24",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0309-6858",
doi="",
url="http://dx.doi.org/"
}