@article{ref1,
title="Alcohol drinking and gallstone disease",
journal="Epidemiology",
year="1995",
author="Thijs, C. and Leffers, P. and Knipschild, P.",
volume="6",
number="3",
pages="338-339",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="1044-3983",
doi="",
url="http://dx.doi.org/"
}