Analytic functions of two non-commuting bounded operators in a Banach space are considered. Sharp norm estimates are established. Applications to operator equations and differential equations in a Banach space are discussed.
"Norm estimates for functions of two non-commuting operators." Rocky Mountain J. Math. 45 (3) 927 - 940, 2015. https://doi.org/10.1216/RMJ-2015-45-3-927