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).
Blueprint diagram for a rolled eye 40/50 rear spring with measurements.
| Identifier | ExFiles\Box 16\7\ Scan230 | |
| Date | 14th May 1930 guessed | |
| ROLLED EYE 40/50 REAR SPRING B 1.375 A 2.625 | ||