"HRB." . . . . "TRB." . . "Ujævnhed" . . "Pavement roughness and rideability" . "Pavement roughness and rideability"@en . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . "National Research Council (É.-U.). Transportation Research Board." . .