A device has an output which is formed by a gearwheel that can be coupled to a gearwheel on a crankshaft of a combustion engine. The device comprises a first auxiliary drive source arranged as an electromotor, which is coupled to the output via a node. A first branch of a drive line is present between the electromotor and the node and a second branch of the drive line is present between the node and the output. The device further includes a second auxiliary drive source arranged as a flywheel which is coupled to the output via the node. A third branch is then present between the flywheel and the node.