/usr/include/ is in libignition-math4-dev 4.0.0+dfsg1-4.
This file is owned by root:root, with mode 0o755.
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/usr/include/ignition/
/usr/include/ignition/math4/
/usr/include/ignition/math4/ignition/
/usr/include/ignition/math4/ignition/math/
/usr/include/ignition/math4/ignition/math/Angle.hh
/usr/include/ignition/math4/ignition/math/Box.hh
/usr/include/ignition/math4/ignition/math/Color.hh
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/usr/include/ignition/math4/ignition/math/Inertial.hh
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/usr/include/ignition/math4/ignition/math/Matrix4.hh
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/usr/include/ignition/math4/ignition/math/SemanticVersion.hh
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/usr/include/ignition/math4/ignition/math/Triangle.hh
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/usr/include/ignition/math4/ignition/math/graph/
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/usr/include/ignition/math4/ignition/math.hh