Stalingrad is an RPG of personal combat during World War II. This is a d10-based, simple game for recreating fast and furious combat engagements.
There are rules for artillery, tanks, minefields, bunkers, detailed breakdowns and more in just under 15 pages, but not background info nor scenarios. You can easily get tons of material elsewhere, so there is little point in including them here.
The game is completely free and you may use, modify and expand it as it pleases you.
You may download Stalingrad in epub format here.
Enjoy it, and watch for enfilade fire!