Box, P. C., & Oppenlander, J. C. (1976). Manual of traffic engineering studies (4a. ed.). Institute of Transportation Engineers.

Box, Paul C., and Joseph C. Oppenlander. Manual of Traffic Engineering Studies. 4a. ed. Arlington: Institute of Transportation Engineers, 1976.

Box, Paul C., and Joseph C. Oppenlander. Manual of Traffic Engineering Studies. 4a. ed. Institute of Transportation Engineers, 1976.