Fair point, but I think even the inclusion of «Jérusalem» (a seldom-performed revision and translation) as a discrete opera is already a slippery slope.
- «Il finto Stanislao» was actually a revision of «Un giorno di regno», not just an alternate title.
- The original version of «I vespri siciliani» was in French («Les vêpres siciliennes»), and the opera was briefly called «Giovanna de Guzman» and «Batilda di Turenne».
- «Il trovatore» was later revised and translated into French as «Le trouvère».
- «Don Carlo» is a translation of the earlier French language opera «Don Carlos».
- «Il finto Stanislao» was actually a revision of «Un giorno di regno», not just an alternate title.
- The original version of «I vespri siciliani» was in French («Les vêpres siciliennes»), and the opera was briefly called «Giovanna de Guzman» and «Batilda di Turenne».
- «Il trovatore» was later revised and translated into French as «Le trouvère».
- «Don Carlo» is a translation of the earlier French language opera «Don Carlos».