Waele, A. d. (1975). Economic problems of traffic peaks: Report of the twenty-ninth Round Table on Transport Economics, held in Paris on 20th and 21st February 1975. European Conference of Ministers of Transport ; sold by the OECD Publications Center].

Waele, Arthur de. Economic Problems of Traffic Peaks: Report of the Twenty-ninth Round Table on Transport Economics, Held in Paris on 20th and 21st February 1975. Paris : [Washington, D. C.: European Conference of Ministers of Transport ; sold by the OECD Publications Center], 1975.

Waele, Arthur de. Economic Problems of Traffic Peaks: Report of the Twenty-ninth Round Table on Transport Economics, Held in Paris on 20th and 21st February 1975. European Conference of Ministers of Transport ; sold by the OECD Publications Center], 1975.