“…Also, eigenvalue regions for discrete and continuous-time positive linear systems have been obtained in [13] by using available information on the main diagonal entries of the system matrix while the absolute stability of discrete-time positive systems has been investigated in [17] when subject to unknown nonlinearities within a class of differential constraints with related positivity properties. Also, the properties of controllability and reachability as well as the stability of positive systems using 2D discrete state-space models and graph theoretic formalisms have been studied in the literature (see, e.g., [7,9,10,12,20,21]). The reachability and controllability as well as the related pole-assignment problem have been also exhaustively investigated for continuous-time positive systems (see, e.g., [7,13,[22][23][24]).…”