One of the Genesis Strategy Guides on this mags db page is actually a Game Players Encyclopedia of Sega Genesis.
There's a seperate page for the Game Players Encyclopedias. It currently only has the Nintendo ones.
The Genesis one says Volume 3, so there's at least 2 others that need adding, and I came across a few Game Boy encycopedias that aren't listed either (oldgamemags.com has Volume 2).
All these Game Player's mags are sooo confusing