C1C1-regularity of solutions for pp-Laplacian problems

In this work, we study C1C1-regularity of solutions for one-dimensional pp-Laplacian problems and systems with a singular weight which may not be in L1L1. On the basis of the regularity result, we give an example to show the multiplicity of positive (or negative) solutions as well as sign-changing solutions especially when the nonlinear term is pp-superlinear.