Which are the biggest selling debut albums?

It is the album Happy Nation, by Swedish pop goup Ace Of Base, the album was titled The sign in North America, it sold ovr 21 million copies since its original release in 1993, and spawned a string of hit singles giving the band number ones in most charts around the world. Actually, Appetite for Destruction by Guns N' Roses has sold almost 28 million copies and it was their debut album.