"March 19, 2004."; Bibliographical references: p. .; Final report;; Sponsored by North Carolina Dept. of Transportation and U.S. Dept. of Transportation, Research and Special Programs Administration
"UNC-WRRI-2003-344."; "May 2003."; Includes bibliographical references (p. 25).; Funded through the Water Resources Research Institute of the University of North Carolina. By Ada Wossink and Bill Hunt.