Simson motorcycle books include the Simson history plus a repair manual.
Simson was a German company which produced firearms, automobiles, motorcycles, and mopeds, founded in 1856. Simson produced more than 300,000 motorcycles of the type AWO 425.
Simson Schwalbe & Co 1955 - 1991 by Frank Ronicke (2007)
Simson by Frank Ronicke (1999)
Simson-Roller Schwalbe: Geschichte, Wartung, Reparatur by Erhard Werner (2004)