As in Norwegian, I have to ask... is Vildanden (the wild duck) not one of his most known/iconic plays outside of Norway? I would say it's easily one of the three defining plays people would know about over here, so it confuses me to see it mentioned like this.
My impression is that a Doll's House and Ghosts are much better known in the English speaking world. Enemy of the People too--probably because of the punchy title.
Interesting, over here I would say et Dukkehjem (a doll's house), Vildanden (the wild duck), and Peer Gynt are his most known works, probably not-very-closely followed by en folkefiende (Enemy of the people). Fascinating.