BMW started delivering motorbikes to the Reichwehr in 1932
in large numbers, probably the most famous BMW motorbike and
sidecar combination was the BMW R 75, which shared many components
with the Zündapp KS 750. Motorcycles were mainly used
for reconnaissance and advance units
German Military Vehicles.
Armoured Fighting Vehicles of Germany World War II.
Encyclopedia of German Tanks of World Two.
For a complete list of sources