@article{ref1,
title="Friction Variations",
journal="Transportation research circular",
year="2009",
author="Burns, J. and Meyer, Walter and Hayhoe, G and Henry, Judith and Ivey, D",
volume="",
number="E-C134",
pages="41-49",
abstract="This paper reviews the state of the art concerning transverse friction, longitudinal friction, skid resistance of pavement markings, friction variation between the paved surface and the shoulder, and seasonal and short-term variations of friction.<p />",
language="",
issn="0097-8515",
doi="",
url="http://dx.doi.org/"
}