@article{ref1,
title="Study to predict which elderly patients will fall shows difficulties in deriving and validating a model",
journal="British medical journal: BMJ",
year="1997",
author="Altman, D. G.",
volume="315",
number="7118",
pages="1309-1309",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0959-8138",
doi="",
url="http://dx.doi.org/"
}