Dyfyniad APA

(1972). Economics of traffic congestion. Open University.

Dyfyniad Arddull Chicago

Economics of Traffic Congestion. Walton Hall: Open University, 1972.

Dyfyniad MLA

Economics of Traffic Congestion. Open University, 1972.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.