Ministry of Transport and Civil Aviation and the Central Office of Information, The Motorway Code — Leaving the Motorway (1958)
“ Leaving the Motorway 32 If you are not travelling to the end of the motorway, watch for the signs warning you of your point of exit; the first sign will be one mile in advance of the slip road to your left, the second half a mile in advance and a third at the exit. 33 To leave a motorway at one of the intermediate exit points, get into the left-hand lane in good time, stay in it, and give a left-turn signal well before you reach the slip road. 34 Reduce speed as necessary in the deceleration lane on the approach to the slip road and not on the motorway itself. ”
