"see robot – definition of robot in Dictionary of South African English". Editor's Note: The origin of 'robot' used as 'traffic light' is from the English translation of the play R.U.R. by Karel Čapek which debuted in England in 1923 which introduced the term 'robot' to an English audience. For a short time in England it was fashionable to use 'robot' for 'traffic light' from the late 1920s, when traffic lights were being installed in England. This usage travelled to South Africa in the early 1930s, when they had their first traffic lights installed, and where it continues to be used almost 90 years later, while 'robot' for 'traffic light' fell out of usage in England. See Foster, B. 1970. The changing English language. Harmondsworth, Middlesex: Penguin.
faqs.org
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"Traffic Signals"(PDF). Institute of Transportation Engineers. September 2007. Archived from the original(PDF) on 27 March 2009. Retrieved 1 April 2009.
"Traffic Signals"(PDF). Institute of Transportation Engineers. September 2007. Archived from the original(PDF) on 27 March 2009. Retrieved 1 April 2009.
Sessions (1971), p. 141. Sessions, Gordon M. (1971). Traffic devices: historical aspects thereof. Washington: Institute of Traffic Engineers. OCLC278619.
Sessions (1971), p. 22. Sessions, Gordon M. (1971). Traffic devices: historical aspects thereof. Washington: Institute of Traffic Engineers. OCLC278619.
Sessions (1971), pp. 27–28. Sessions, Gordon M. (1971). Traffic devices: historical aspects thereof. Washington: Institute of Traffic Engineers. OCLC278619.
Sessions (1971), p. 143. Sessions, Gordon M. (1971). Traffic devices: historical aspects thereof. Washington: Institute of Traffic Engineers. OCLC278619.
