APA (7th ed.) Citation

Helliar-Symons, R. D., & Ray, S. D. (1986). Automatic close-following warning sign: Further trials. Transport and Road Research Laboratory.

Chicago Style (17th ed.) Citation

Helliar-Symons, R. D., and S. D. Ray. Automatic Close-following Warning Sign: Further Trials. Crowthorne, Berkshire: Transport and Road Research Laboratory, 1986.

MLA (9th ed.) Citation

Helliar-Symons, R. D., and S. D. Ray. Automatic Close-following Warning Sign: Further Trials. Transport and Road Research Laboratory, 1986.