“…If, on the contrary, the pair (A, B) is not stabilizable, or the pair (A, C) is not detectable (for example, if B = 0 or C = 0), then system (1) can be stabilized neither by linear static output feedback controls, nor by LH-controls. Thus, the assumption posed on system (1) that B, C are nonzero vectors is indeed essential and provides no loss of generality: only in this case LH-controls can do the stabilization job better than linear static output feedback controls (see [5], [4] for the details).…”