1. Regularity properties of perturbed Hille–Yosida operators and retarded differential equations;Bátkai;Semigroup Forum,2002
2. S. Boulite, S. Hadd, L. Maniar, The critical spectrum and stability of population equations with diffusion in unbounded domains, Discrete Contin. Dynam. Systems, in press
3. Semigroups of Operators and Approximation;Butzer,1995
4. An Introduction to Infinite-Dimensional Linear Systems Theory;Curtain,1995
5. Some generation results for perturbed semigroups;Desch,1989