Praveen Kumar Pankaj Rai Amit Kumar Choudhary Order Reduction of z-Domain Interval Systems by Advanced Routh Approximation Method. 6911-6930 2024 November 43 Circuits Syst. Signal Process. 11 https://doi.org/10.1007/s00034-024-02799-8 db/journals/cssp/cssp43.html#KumarRC24 streams/journals/cssp