http://www.workzonesafety.org/research/record/9992 Comments for "Evaluating Effectiveness of Dynamic Speed Display Signs in Transition Zones of Two-Lane Rural Highways in Pennsylvania" en http://www.workzonesafety.org/research/record/9992 http://www.workzonesafety.org/research/record/9992#comment Books and Reports Intelligent Transportation Systems Rural Highways Traffic Speed Variable Speed Limit Systems Wed, 28 Oct 2009 09:58:24 -0500 j-whipple1 9992 at http://www.workzonesafety.org