Calderón-Zygmund theory is a classical topic in the analysis of partial differential equations,
and deals with determining, possibly in a sharp way, the integrability and differentiability …

We examine the geometry of the level sets of particular horizontally $ p $-harmonic functions
in the Heisenberg group. We find sharp, natural geometric conditions ensuring that the level …

We consider autonomous integral functionals on the Heisenberg group which have
quadratic growth from below and q-growth from above. We find an upper bound on q which …

We consider integral functionals in the Heisenberg group, whose convex C 2-integrand has
quadratic growth from below, and growth of order q> 2 from above. We prove Hölder …

We study the regularity problem for solutions of quasi-linear subelliptic equations of
divergence form [special characters omitted] where X i (i= 1,···, 2n) are horizontal vector …

Regularity of solutions for the non-degenerate p-Laplacian equation on the Heisenberg group
for p<2 Page 1 Adv. Calc. Var. 3 (2010), 115 – 148 DOI 10.1515/ACV.2010.007 © de Gruyter …