@article{ref1,
title="Physical work capacity in men and women aged 18 to 65",
journal="Scandinavian journal of social medicine",
year="1979",
author="Jonsson, B. G. and Astrand, I.",
volume="7",
number="3",
pages="131-142",
abstract="<p>[Abstract unavailable]</p> <p>Language: en</p>",
language="en",
issn="0300-8037",
doi="",
url="http://dx.doi.org/"
}