Although I can't be sure, I do suspect that it's fake (99.9% sure). As has been pointed out many, many times before, such a thing can easily be done in PhotoShop, so if anyone wants to fake something like this, it's a piece o' cake. The Britney cover doesn't even look good, pretty amateur.
On top of that, the pictures used on Britney's cover are from a magazine photoshoot and it's highly unlikely that they would be used on actual coverart then.
So actually I'm sure it's fake.
Fake.
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