See A.G. Otto. = A.G. OTTO.- Alemania. Tambien conocida como AGO.

-Factory situated in Munich. Before the First World War they made three water cooled models with upright cylinders.

-The 50 and 100 CV models with four cylinders.
-The 75 CV with six cylinders.

From appendix 9: AGO stands for "Gustav Otto Aeromotor". He is the inventor of the Otto four-stroke cycle based on the Carnot-heat-cycle principle.

-Gustav began his AGO company in 1911, ordering the engine construction to the manufacturer Hans Geisenhof and the first 100 hp engine left the factory in 1912.

“Geisenhof with the AGO 100 CV engine”

“AGO 50 CV”

The 50 cv engine was also manufactured by Hans Geisenhofer for Gustav Otto (AGO).