@article{ref1,
title="Work hygiene of tractor workers",
journal="Zdrowie Publiczne - Polskie Towarzystwo Higjeniczne",
year="1954",
author="Freytag, J.",
volume="5",
number="",
pages="403-405",
abstract="<p>[Abstract unavailable]</p> <p>Language: en</p>",
language="en",
issn="0044-2011",
doi="",
url="http://dx.doi.org/"
}