Maximal, potential and singular operators in the local "complementary"   variable exponent Morrey type spaces
  We consider local "complementary" generalized Morrey spaces ${\dual \cal M}_{\{x_0\}}^{p(\cdot),\om}(\Om)$ in which the $p$-means of function are controlled over $\Om\backslash B(x_0,r)$ instead of $B(x_0,r)$, where $\Om \subset \Rn$ is a bounded open set, $p(x)$ is a variable exponent, and no monotonicity type conditio is imposed onto the function $\om(r)$ defining the "complementary" Morrey-type norm. In the case where $\om$ is a power function, we reveal the relation of these spaces to weighted Lebesgue spaces. In the general case we prove the boundedness of the Hardy-Littlewood maximal operator and Calderon-Zygmund singular operators with standard kernel, in such spaces. We also prove a Sobolev type ${\dual \cal M}_{\{x_0\}}^{p(\cdot),\om} (\Om)\rightarrow {\dual \cal M}_{\{x_0\}}^{q(\cdot),\om} (\Om)$-theorem for the potential operators $I^{\al(\cdot)},$ also of variable order. In all the cases the conditions for the boundedness are given it terms of Zygmund-type integral inequalities on $\om(r)$, which do not assume any assumption on monotonicity of $\om(r)$. 
Vagif S. Guliyev, Javanshir J. Hasanov, Stefan G. Samko
math.FA