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).
List of Bosch magnetos and spark plugs with their associated reference numbers.
| Identifier | ExFiles\Box 34\3\ Scan004 | |
| Date | 1st March 1918 guessed | |
| X.2635 BOSCH. X.427. Bosch Magneto. X.796. * * X.878. * Spark, plugs 3 point type. X1020. * ZR6 Dual Ignition Magneto. X1423. R.R. Magneto - Bosch type. X2635. Bosch spark. plugs 4 point type. X2796. * HL. 6-Cylinder type magneto. X2862. * 2-Cylinder light weight magneto. | ||