Further discussion on impulse energy approximation
Recent criticisms by Rao about impulse energy approximation are answered in detail. Further ideas are put forward as to how weighted energy parameters may be used to determine the reduced models for step inputs.
Lucas, T.N. 1987. Further discussion on impulse energy approximation. IEEE Transactions on Automatic Control. 32(2): pp.189-190. Available from http://dx.doi.org/10.1109/TAC.1987.1104542