@article{ref1,
title="Certain problems touching some points of navigation",
journal="Philosophical transactions of the Royal Society of London (1665)",
year="1665",
author="",
volume="1",
number="13",
pages="215-218",
abstract="<p>[Abstract unavailable]</p>",
language="",
issn="0370-2316",
doi="",
url="http://dx.doi.org/"
}