@article{ref1,
title="Development of an emergency zone sign",
journal="Transportation research record",
year="1993",
author="Pietrucha, Martin T.",
volume="1421",
number="",
pages="36-44",
abstract="The concept of having a separate category of traffic sign to control traffic in emergency situations is advanced. This category is referred to as an emergency zone sign (EZS). A rationale is provided for having this category of sign and for developing a family of emergency zone signs. Detail is provided on the sign messages, shapes, and colors.     Record URL:        http://onlinepubs.trb.org/Onlinepubs/trr/1993/1421/1421-005.pdf<p /><p>Language: en</p>",
language="en",
issn="0361-1981",
doi="",
url="http://dx.doi.org/"
}