Der vertragliche Schuldbeitritt im Gefüge gegenseitiger Dauerschuldverhältnisse - Klaus Bartels - Google Books

https://books.google.de/books?id=_BW9_K23GDwC&printsec=frontcover&dq=Schuldbeitritt&hl=de&sa=X&ved=0ahUKEwiu_NKTxOHZAhXLWSwKHQwI

English summary: Klaus Bartels describes the dogmatic position of the so-called secondary obligor, which is somewhere between complete contract participation and providing a single security for a debt, such as a guarantee. Whereas legal theory sees the…