You can go here and download a OPS manual, sorry this one is not in german, but if you prefer there might be a copy available out there.
https://kubota.ca/getmedia/a025170d...M5-091,-M5-111-CAB-WSM-EN-3B79199712?ext=.pdf
For the WSM (Service Manual) for that model and series of tractor your going to have to contact your dealer /selling agent.
For others reading, the M5001 is a BIG tractor, M5091 (95HP) , M5111 (113HP),
They are called the M5 series, better know in the US and CA as M5-091 and M5-111.
This is a real defection from the normal Kubota numbering system.