[petsc-users] PETSc, free software and using cost

[Bentejui Medina]

Hi all,
i'm using PETSc for a project at the university. My software is opensource (GPL) , can I distribute my software including PETSc? What license use PETSc?

I need to create a teorical invoice for the project. Has PETSc any cost?, any cost if a use it for a commercial product?

Thanks a lot.