“…The transfer function having interval parameters is known as interval systems. Some practical systems, mathematically modelled as interval systems, are cold rolling mill, DC shunt motor, oblique wing aircraft, and Riverol-Pilipovik water treatment [19], [20]. The interval transfer functions of cold rolling mill, DC shunt motor, oblique wing aircraft, and Riverol-Pilipovik water treatment are given, respectively, in (1), (2), (3) and (4).…”