From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
On the service dates and 'L' shaped rings for two 25/30HP London Trials Cars.
| Identifier | ExFiles\Box 107\1\ scan0445 | |
| Date | 7th July 1937 | |
| Rm.{William Robotham - Chief Engineer} from Mx.{John H Maddocks - Chief Proving Officer} b.60 Mx{John H Maddocks - Chief Proving Officer}5/T7.7.37 25/30HP London Trials Cars. The dates these two cars were put into service are as follow - GWN- 2. 12.4.37 GWN-54 3.2.37 Both cars are fitted with 'L' shaped rings. | ||