@article{ref1,
title="Transitional grading of highway slopes",
journal="Highway Research Board Roadside Development Committee reports",
year="1949",
author="Dubois, R.s.",
volume="",
number="",
pages="-",
abstract="<p>[Abstract unavailable]</p>",
language="",
issn="",
doi="",
url="http://dx.doi.org/"
}