@article{ref1,
title="Description of a Spring-Block, Designed to Assist a Vessel in Sailing",
journal="Transactions of the American Philosophical Society",
year="1793",
author="Hopkinson, Francis",
volume="3",
number="",
pages="331-331",
abstract="<p>[Abstract unavailable]</p>",
language="",
issn="0065-9746",
doi="10.2307/1004885",
url="http://dx.doi.org/10.2307/1004885"
}