Yeah, I noticed that with a few other titles too. Could be that they didn't care a lot about the years on the boxes. Or the multilingual version came so close after the single-language version (in the same year).
Or, both variations existed at the same time - which would not make any sense in my opinion, but who knows ... 
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In fact they are still three variants of each game, if I am right: US, Euro single language and Euro multi language. I have no concrete information how much time was between the Euro single and multi versions, but I think it was not much time, a year, maybe even less. Wonder why they did this ...
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Thanks for the Canadian addition, but basically those were the same as the US versions, except for the additional French text, right?
Different cover artworks for the single language versions suck though. Those guys were crazy. They never thought of later collectors like us, they should have made it easier for us ...
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