@article{ref1,
title="Perforation of the esophagus. A 30 year review",
journal="Journal of thoracic and cardiovascular surgery",
year="1973",
author="Berry, B. E. and Ochsner, J. L.",
volume="65",
number="1",
pages="1-7",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0022-5223",
doi="",
url="http://dx.doi.org/"
}