Gallery/gallery list is displayed twice

I've created serveral gallery archives and galleries and set up gallery lists and a gallery view as described in the documentation. Now the gallery lists and galleries are displayed twice. I'm looking around for a hour but habve no idea how to fix this. The html code is simply rendered twice - identically. Maybe someone can give me a hint?

cu
Jan

That could happen if you have it inserted as a module in an article and also in the layout. Normally it wont do that..

Thanks for the hint! The module "Article" was booked twice in the main column. I'm pretty sure, that I didn't do that - strange.