There was I believe a researcher at Reading University in the UK who did a bunch of work on vertical axis turbines.
They actually built a couple of fairly large 'H' configuration units.
Had trouble with the torque tubes busting due to the cyclic loading as I recall.
A few good google searches should get you on the right track, I've researched this a couple of times but no books spring to mind.
KENAT, probably the least qualified checker you'll ever meet...