Concert· Düsseldorf
BOSY Extra: Gemeinsam Klingen – ein Mitsingkonzert
I don't have any information about an event called "BOSY Extra" — it's not something I recognize, and no details were included in your message. Could you share more context, like a description, flyer, or details about the event? Once you do, I'd be happy to write a concise 1–2 sentence summary for you.