Dear flateric,
May I make a minor "poke" at terminology?
In the West. those are called "three surface" wings. Many 3 surface prototypes have flown, but only the Italian Piaggio Avanti made it to production.
Aerodynamically, most (e.g. Piaggio Avanti) three-surface configurations are more like conventional airplanes with a horizontal tail "lifting" downwards, a conventional wing lifting upwards and a canard also lifting upwards.
Avanti has three surfaces because the main spar is routed aft of the cabin pressure vessel, making it nose-heavy. Piaggio added a second lifting surface to lift the nose and restore balance. The canard has no moving controls, so it is purely a lifting surface ... an extra bit of the main wing in an unusual location.
IOW Piaggio SPLIT the main lifting surface into two pieces to route them around the cabin, but still keep the centre-of-lift close to the centre-of-gravity.
Other three-surface planes may have a second lifting surface on the nose (e.g. Wren STOL conversion of Cessna 182) with control surfaces, but those control surfaces are merely flaps (only deflect downwards) to increase lift at low airspeeds. In the case of Wren STOL, they need more nose-up trim at slow landing speeds.