On necessary and sufficient conditions for Lp-estimates of Riesz transforms associated to elliptic operators on Rn and related estimates

On Necessary and Sufficient Conditions for L^p-estimates of Riesz Transforms Associated to Elliptic Operators on R^n and Related Estimates (Memoirs of the American Mathematical Society)

Heat kernels and analysis on manifolds, graphs, and metric spaces

Boundary Value Problems and Hardy Spaces for Elliptic Systems with Block Structure