@article{ref1,
title="Motor evoked potential warning criteria",
journal="Journal of clinical neurophysiology",
year="2017",
author="MacDonald, David B.",
volume="34",
number="1",
pages="1-3",
abstract="<p>[Abstract unavailable]</p> <p>Language: en</p>",
language="en",
issn="0736-0258",
doi="10.1097/WNP.0000000000000346",
url="http://dx.doi.org/10.1097/WNP.0000000000000346"
}