Two posters from the next year's Sonisphere festivals around Europe just leaked. I found on the official websiteσ of Sonisphere two previews of Milan's and Amneville's gig in Italy and France. Maiden England is posted for Italy's Milan, Saturday 8 of June 2013 and France's Amneville, Saturday 8 and Sunday 9 of June 2013, obviously Iron Maiden are headlining the second day since the 8th of June are headlining in Italy.

Those posters can't be fake since I personally (Manolis) found them on the Official Sonisphere website (those still under construction).

ironmaidenfc.gr