“…On the other hand, robust observation (or estimation) [5,26,9,28,30] is concerned with the state reconstruction when the plant model has uncertain parameters and is described by ordinary differential equations (ODE) or equivalent representation. Following the third approach based on FDS, results on estimating the state of uncertain system with statedelay are developed in [18] and related work can be found in [21]. An integral part of FDS [11][12][13]32] is the class of neutral-type systems which can be found in several applications including, but not limited to, chemical reactor, rolling mill, infeed grinding, lossless transmission lines and hydraulic systems.…”