Hardwood on concrete

Try any of the hardwood flooring sites. They will have their specs for installation over concrete. Here is the one for Armstrong:

Then install the flooring on the substrate.

I don't know of any hardwood flooring manufacturer that will warranty solid HW floors directly onto concrete.

Yikes! If you want hardwood on a slab, you'll need to install the engineered hardwood. Otherwise, I would suggest installing 3/4 ply with a moisture membrane if you install solid.

Sorry, it is not recommended unless you take special steps, like putting insulation and vapor barrier between 2 x 4 sleepers. You lose a lot of headroom that way and a PITA in places. You can use engineered hardwood though, along with the proper barrier.