“…This subject has been considered in many papers and monographs (Kaczorek and Klamka, 1986;Kaczorek, 2014;Klamka, 1991;2009;2014). LTI (linear time-invariant) systems theory deals with numerous types of systems, e.g., positive (Kaczorek 2002;2013a;2013c;2011d), descriptor (Campbell et al, 1976;Dai 1989;Dodig and Stosic, 2009;Guang-Ren, 2010;Van Dooren, 1979;Van Dooren and Beelen, 1988) or fractional (Nishimoto, 1984;Oldham and Spanier, 1974;Podlubny, 1999).…”