NEW YORK (AP) – The Rolling Stones are extending their set of shows to mark their 50th anniversary. And they extending the invitation for other artists to join in one last performance to mark the occasion. The Stones will play Saturday at the Prudential Center in Newark, New Jersey. Joining them on the show will be Bruce Springsteen, Lady Gaga and The Black Keys – and the show will be available on pay per view. The Stones have already played London and New York on their “50 and Counting” tour. They will also play in Newark on Thursday. Tomorrow night, they perform at the “12-12-12″ concert at Madison Square Garden. Proceeds from that show will help victims of Superstorm Sandy.