1. Ahlfors L. V. (1979) Complex Analysis: An Introduction to the Theory of Analytic Functions of One Complex Variable, 3rd edn. USA: McGraw-Hill.
2. Zeros of sampled systems
3. Åström K. J. , Wittenmark B. (1997) Computer-Controlled Systems: Theory and Design. USA: Prentice Hall.
4. On zeros of pulse transfer functions
5. Static output feedback stabilization for SISO systems and related problems: solutions via generalized eigenvalues;Chen;Control Theory Adv. Technol.,1999