@article{ref1,
title="Static or frictional electricity and the discovery of direct current",
journal="Puerto Rico health sciences journal",
year="1997",
author="Del Castillo, J.",
volume="16",
number="4",
pages="411-416",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0738-0658",
doi="",
url="http://dx.doi.org/"
}