Connecting heterogeneous documents of performing arts from distinct collections. The case of opera

Opera, as a performative art, is composed by many texts simultaneously. A literary text resides in the libretto, music is transcribed in music scores, and scenography or costumes are represented by sketches, among other elements. Collections bring together librettos, music scores, sketches and various other documents, including sound and audiovisual recordings, usually from different works. Normally, no information is provided regarding the section of the work to which a single item is related, or the available information is ambiguous. By way of example, according to cataloguing rules both the adagio and the cabaletta of Violetta’s aria in the first act are just part of Verdi’s “La Traviata” and simply cannot be distinguished from each other. An index would therefore be necessary to correctly reference a document to an identified position within a specific work. Coherently with the Functional Requirements for Bibliographic Records (and the Library Reference Model), we propose an index capable of mapping a document to the specific section of a work from which it originates. Furthermore, an authority file is created to precisely identify each extract of the work. This unifying approach facilitates the connection of distinct archives and collections across different institutions. The advantages for users are self-evident: the fragmented view is consolidated into a cohesive whole, ambiguity is eliminated, standardized search capabilities are enabled, and results can be enriched. Examples from the collections of historical records housed within the Department of Cultural Heritage at the University of Bologna will be suggested.