Advisory Committee on Traffic Signs for Motorways, Traffic Signs for Motorways (1962)
“ A special problem arises here since traffic will arrive at the terminal junction (usually in the form of a roundabout) without leaving the main carriageway of the motorway. It is therefore imperative that adequate warning should be given so that drivers, though still on the motorway, will reduce speed to the greater extent which is necessary to enable them to negotiate the junction in safety. ”
