World Bank
United States. General Accounting Office
National Research Council (U.S.) Transportation Research Board
Canada
United States. Bureau of Labor Statistics
William C Epstein
Nick Capachi
Rajib Basu Mallick
South Carolina. General Assembly. Legislative Audit Council.
Johnson, James H.
A. T. Papagiannakis
United States. Congress. House. Committee on Foreign Affairs
Emmanuel Bamfo-Agyei
Roads and Transportation Association of Canada
S. D. Anderson
José Diogo Mascarenhas Neto
American Association of State Highway and Transportation Officials.
Unknown Author
K. A. Busurin