No offense, Dejean, but in the future, you need to do your homework before you buy. Know as much as possible on whatever you're after. Then you'll be less likely to get burnt.
As with most bootlegs, you're looking for discrepancies in size. The feel of the paper. The weight of the paper. Are any credits missing. Are the credits clear. Is there any blur, or misalignment. A whole host of things, really.
If you do go thru with it, I'm sure collectors here will compare posters with you.