The author presents the book of Bernhard Bischoff (Salzburger Formelbücher und Briefe aus Tassilonischer und Karolingischer Zeit, Sitzungsberichte der Bayerischen Akademie der Wissenschaften, phil.-hist. Klasse, Heft 4, München 1973). Separately he deals with the texts referring to the Carinthian history. The main attraction he sees in the possibility that the lost code »Liber traditionum«, the copy of which Bischoff has published, in its origin comprised also two Slavic texts from the second part of the 8th century, possibly religious formulars for missionary activity among the Carinthian Slavs.