@article{ref1,
title="America's covered bridges: spanning the years",
journal="American city and county",
year="1998",
author="Black, T.",
volume="113",
number="3",
pages="9 p.-9 p.",
abstract="In certain regions of the country, particularly the Northeast and Midwest, the covered bridge survives as an enduring reminder of America's rural, rustic past. At one time, the United States had as many as 12,000 covered bridges. Current estimates range from 850 to 1,000. Pennsylvania, with 219 covered bridges, about 150 which are still in use, has the most. Time and again, covered bridges have been rebuilt or refurbished following floods, fires, ice jams, and windstorms. Refurbishment projects often call for maximum use of original parts and replacement parts that are as close to authentic timber as possible. Regardless of which type of wood is used, bridge restorations are not cheap. About 95% of the nation's covered bridges are &quot;off-system,&quot; meaning they are not a part of the federal highway system. Many are open to cars and light trucks, but others have been designated strictly for pedestrians. A dramatic reduction in new covered bridge construction can be written off as part of the &quot;price of progress.&quot;<p />",
language="",
issn="0149-337X",
doi="",
url="http://dx.doi.org/"
}