What is with the covers for the Final Countdown?

I keep seeing covers by Children of Bodom for The Final Countdown, but EVERYONE says they did not cover the song.
Why is it under their name and who is it really besides Europe, Dispatched, Norther, who else?

Btw, I downloaded 2 from norther and 2 from COB and they sound EXACTLY the same.

The cover you have is by Norther. COB have done a lot of covers, but not that one.

EUROPE is the original artist of the song. ive never heard any covers of it though.