@article{ref1,
title="Normal motor development",
journal="Physical therapy",
year="1965",
author="Twitchell, T. E.",
volume="45",
number="",
pages="419-423",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0031-9023",
doi="",
url="http://dx.doi.org/"
}