@article{ref1,
title="Depressive symptoms associated with poor outcome after lumbar spine surgery: pain and depression impact on each other and aggravate the burden of the sufferer",
journal="Scandinavian journal of pain",
year="2017",
author="Breivika, H.",
volume="12",
number="1",
pages="e57-e57",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="1877-8860",
doi="10.1016/j.sjpain.2016.04.006",
url="http://dx.doi.org/10.1016/j.sjpain.2016.04.006"
}