@article{ref1,
title="Control of states of consciousness. II. Attainment through external feedback augmenting control of psychophysiological variables",
journal="Archives of general psychiatry",
year="1971",
author="Gaarder, K.",
volume="25",
number="5",
pages="436-441",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0003-990X",
doi="",
url="http://dx.doi.org/"
}