Had to go back and look to remember which it was,, then find what I wrote on it !! Didn`t find much really,, I enlarged the letter you had and all it said was that it was a monoprint with no proofs since this can only be done once !! That means that yours is probably done as I told you before or something similar and is an original !! That still doesn`t mean its worth any more than you paid for it !! Tried to find Sterling Graphics and there are a bunch across the U.S. using that name and since there is no letterhead with the location on it, only way it is helpful is if you can find the one that did it !! Truthfully,, I wouldn`t go to the trouble since this Chin has no sales record and is more than likely a local hobby artist or a wanna be artist !! Evidently he didn`t do well or there would be a sales record somewhere !! But,, lot of people like botanical prints !! Would have been better had he written the source of the material on the print !! Don`t think he did ??