/usr/share/dolfin/demo/undocumented/elastodynamics/ is in dolfin-doc 2016.2.0-2.
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/usr/share/dolfin/demo/undocumented/elastodynamics/cpp/
/usr/share/dolfin/demo/undocumented/elastodynamics/cpp/CMakeLists.txt
/usr/share/dolfin/demo/undocumented/elastodynamics/cpp/DG0_eps_xx.h
/usr/share/dolfin/demo/undocumented/elastodynamics/cpp/DG0_eps_xx.ufl
/usr/share/dolfin/demo/undocumented/elastodynamics/cpp/ElastoDynamics.h
/usr/share/dolfin/demo/undocumented/elastodynamics/cpp/ElastoDynamics.ufl
/usr/share/dolfin/demo/undocumented/elastodynamics/cpp/main.cpp
/usr/share/dolfin/demo/undocumented/elastodynamics/dolfin_fine.xml.gz
/usr/share/dolfin/demo/undocumented/elastodynamics/python/
/usr/share/dolfin/demo/undocumented/elastodynamics/python/demo_elastodynamics.py