I believe this one is by far one of the rarest TSR items I've found in over 25 years of intensive collecting. Apparently it is a second, almost totally unknown, finnish translation of the D&D rules. It was published by a company called Toptronics,

These Toptronics used to import and sell computer games in
Finland. Toptronics was sold/merged to Pan Vision Distribution Group in
2005. The printing info on the backside says that it was published in
1992. The other translation (Red Cover) was published I believe in 1990.

As I understand, this black and white fanzine-sized product was handed
out to customers who bought a specific computer game based on Dungeons & Dragons, but I do not know for sure which game was that.

Agent Cooper wrote in Second, almost unknown finnish translation of D&D:I'm amazed at how many foreign language editions there are.

I wonder how many languages D&D was published in?

Good question!  According the Wikipedia web-page regarding all the D&D editions(Editions of Dungeons & Dragons - Wikipedia, the free encyclopedia), apparently there are no reference sources for that information, and the entire section could be re-done.  Therefore, for someone interested in making their mark upon the world, a little research and effort could figure all that out, reference it, and be forever famous....sort of.

The 13 languages I have heard about with little research are below (but I am guessing there are other translations).
French
Portuguese
Italian
Chinese
Japanese
Finnish
Danish
German
Korean
Norwegian
Swedish
Hebrew
Spanish (In Hispanic America it's called "Calabozos y Dragones," and in Spain it's called "Dragones y Mazmorras"

I would not count the two Spanish titles as two languages just like British and American editions would not be two different language editions.  Although, there's probably someone around here who would argue otherwise.  

Echohawk wrote in Second, almost unknown finnish translation of D&D:

benjoshua wrote in Second, almost unknown finnish translation of D&D:The 13 languages I have heard about with little research are below (but I am guessing there are other translations).

According to this ENWorld discussion, at least Dutch, Hungarian, Polish and Turkish can be added to that list.

I can confirm that. Own those versions myself.