Schwarzian derivatives, the Poincaré metric and the kernel function.
We prove some optimal estimates of Hölder-logarithmic type in the Hardy-Sobolev spaces , where , and is either the open unit disk or the annular domain , of the complex space . More precisely, we study the behavior on the interior of of any function belonging to the unit ball of the Hardy-Sobolev spaces from its behavior on any open connected subset of the boundary of with respect to the -norm. Our results can be viewed as an improvement and generalization of those established...