1. Ch Kunstmann and Perturbation theorems for maximal Lp - regularity Scuola Norm Sup Pisa Cl;Weis;Ann Sci,2001
2. Functional Analysis and Semi - Groups Providence;Hille;Amer Math Soc,1957
3. Linear parabolic problems involving measures Cien Serie A;Amann;Rev Mat,2001
4. Coerciveness inequalities for abstract parabolic equations Soviet;Sobolevskii;Math,1964
5. On the closedness of the sum of two closed operators;Dore;Math Z,1987