@article{ref1,
title="Results of fitness examination of ship's nautical officers in the age 45 to 65 years",
journal="Bulletin of the Institute of Maritime and Tropical Medicine in Gdynia",
year="1989",
author="Ebert, H. and Mehlhorn, D.",
volume="40",
number="3-4",
pages="131-134",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0324-8542",
doi="",
url="http://dx.doi.org/"
}