/usr/share/dolfin/demo/documented/cahn-hilliard/ is in dolfin-doc 2016.2.0-2.
This file is owned by root:root, with mode 0o755.
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/usr/share/dolfin/demo/documented/cahn-hilliard/cpp/
/usr/share/dolfin/demo/documented/cahn-hilliard/cpp/CMakeLists.txt
/usr/share/dolfin/demo/documented/cahn-hilliard/cpp/CahnHilliard2D.cpp
/usr/share/dolfin/demo/documented/cahn-hilliard/cpp/CahnHilliard2D.h
/usr/share/dolfin/demo/documented/cahn-hilliard/cpp/CahnHilliard2D.ufl
/usr/share/dolfin/demo/documented/cahn-hilliard/cpp/CahnHilliard3D.cpp
/usr/share/dolfin/demo/documented/cahn-hilliard/cpp/CahnHilliard3D.h
/usr/share/dolfin/demo/documented/cahn-hilliard/cpp/CahnHilliard3D.ufl
/usr/share/dolfin/demo/documented/cahn-hilliard/cpp/main.cpp
/usr/share/dolfin/demo/documented/cahn-hilliard/python/
/usr/share/dolfin/demo/documented/cahn-hilliard/python/demo_cahn-hilliard.py