National Research Council (U.S.). Highway Research Board, Moyer, R. A., Shupe, J. W., & Morgan, A. D. (1951). Roughness and skid resistance: Presented at the Thirtieth Annual Meeting, 1951. Highway Research Board.
Cita Chicago (17th ed.)National Research Council (U.S.). Highway Research Board, Ralph A. Moyer, John W. Shupe, i A. Duke Morgan. Roughness and Skid Resistance: Presented at the Thirtieth Annual Meeting, 1951. Washington, D.C: Highway Research Board, 1951.
Cita MLA (9th ed.)National Research Council (U.S.). Highway Research Board, et al. Roughness and Skid Resistance: Presented at the Thirtieth Annual Meeting, 1951. Highway Research Board, 1951.
Atenció: Aquestes cites poden no estar 100% correctes.