http://naca.larc.nasa.gov/reports/19...ca-tn-2525.pdf

The above link should take you directly to the specific report that I
mentioned.

(If it fails for some reason, searching for "2525" on the NACA
technical report server will pull it up.)

Also, have you tried a Google search on "dynamic stall" yet?

I did in the past, but not recently. I vaguely recall that
helicopters came up the most.

My Wayne Johnson's "Helicopter Theory" discusses it in the context of
helicopters, but in the airplane case, Hoerner's "Fluid Dynamic Lift"
goes into it a bit. "Theory of Wing Sections" also discusses it, and
one or two other references in various aerodymamics books.