@article{ref1,
title="Work shifts, sleep and biological rhythms",
journal="Revista da Associacao Medica Brasileira (1992)",
year="1998",
author="Gaspar, S. and Moreno, C. and Menna-Barreto, L.",
volume="44",
number="3",
pages="239-245",
abstract="<p>[Abstract unavailable]</p><p>Language: pt</p>",
language="pt",
issn="0104-4230",
doi="",
url="http://dx.doi.org/"
}