Nisciuna paggena soddisfà sti criterie.
- ↑ 1,0 1,1 Gemeinsame Normdatei
- ↑ 2,0 2,1 data.bnf.fr
- ↑ 3,0 3,1 SNAC
- ↑ 4,0 4,1 Internet Broadway Database
- ↑ 5,0 5,1 International Music Score Library Project
- ↑ 6,0 6,1 todotango.com
- ↑ 7,0 7,1 Archivio Storico Ricordi