Junkers Motorenwerke AG (Jumo)
Hugo Junkers was researching internal combustion engine improvements as early as 1888, co-founded his first engine company in 1890, and patented the opposed-piston Diesel engine in 1892. Other Junkers companies began building aircraft and experimental aircraft engines during WWI. Junkers Motorenwerke AG (Jumo) produced successful aircraft Diesel, spark-ignition and gas turbine engines through WWII.
More information about Hugo Junkers and his companies is available from the Hugo Junkers Homepage
The Junkers Jumo 213 Engine
Junkers Jumo 222 Intelligence Reports
1943 paper by Helmut Schelp comparing turbosupercharged Jumo 222 performance with gas turbines.
Junkers Jumo 211
Robert Inkol has kindly contributed the following manual pages.