@article{ref1,
title="Undertow, rip tide or "rip current"",
journal="Science",
year="1936",
author="Shepard, F. P.",
volume="84",
number="2173",
pages="181-182",
abstract="<p>[Abstract unavailable]  Keywords: Drowning; Drowning Prevention; Water Safety </p> <p>Language: en</p>",
language="en",
issn="0036-8075",
doi="10.1126/science.84.2173.181",
url="http://dx.doi.org/10.1126/science.84.2173.181"
}