Add to ORKGInternational audienceThe study of the authorities in the Liber glossarum is conducted here through examination of the labels of sources. These labels or "tags" are interesting both for the history of the text and its constitution and for research in general, because the Liber glossarum is an observation point on the situation of rare texts at the time they enter into circulation in the medieval West, or on the contrary at the time they disappear forever. The tags confirm the assignment of the De Haeresibus to Isidore of Seville, and put us on the track of a textbook by the same author, called the Liber artium. They are also indicative of compilation processes, suggesting the use of Isidorian records in which the name of the ultimate source...