APA

U.S. Department of Transportation. NHTSA. Office of Driver and Pedestrian Programs. Enforcement and Emergency Services Division, . (1979). 55 mph fact book 1979. Washington DC: U.S. Department of Transportation. NHTSA. Office of Driver and Pedestrian Programs. Enforcement and Emergency Services Division.

Chicago

U.S. Department of Transportation. NHTSA. Office of Driver and Pedestrian Programs. Enforcement and Emergency Services Division, . 1979. 55 mph fact book 1979. Washington DC: U.S. Department of Transportation. NHTSA. Office of Driver and Pedestrian Programs. Enforcement and Emergency Services Division.

Harvard

U.S. Department of Transportation. NHTSA. Office of Driver and Pedestrian Programs. Enforcement and Emergency Services Division, . (1979). 55 mph fact book 1979. Washington DC: U.S. Department of Transportation. NHTSA. Office of Driver and Pedestrian Programs. Enforcement and Emergency Services Division.

MLA

U.S. Department of Transportation. NHTSA. Office of Driver and Pedestrian Programs. Enforcement and Emergency Services Division, . 55 mph fact book 1979. Washington DC: U.S. Department of Transportation. NHTSA. Office of Driver and Pedestrian Programs. Enforcement and Emergency Services Division. 1979.