The shown lorry is a Fross-Büssing of the 6 - 6.5 tons payload class. It could be a Fross-Büssing V FB Greif which was offered with diesel and petrol engines from 75 to 100 HP.
The lorries of Fross-Büssing corresponded to the lorries of Büssing-NAG to a large extent but Fross-Büssing made own engine bonnets and driver’s cab’s. Both shown lorries were of the same type. Most probably, they originated from the Reichsbahn.