Written form
Terminationand termination agreements must be signed. They are subject to the so-called written form requirement. It is mandatory and cannot be excluded by contract. A Termination Without the original signature of your employer or a representative who is authorized to make personnel decisions, the Termination ineffective. A Termination by text message, for example, is invalid. The lack of written form can also be remedied after the expiry of the otherwise relevant Limitation period within three weeks.
English 
German