/usr/include/ is in libdianewcanvas2-dev 0.6.10-5.3.
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/usr/include/dia-newcanvas-1.0/
/usr/include/dia-newcanvas-1.0/dia-newcanvas/
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-newcanvas.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-item.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-group.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-point.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-line.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-rectangle.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-polygon.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-ellipse.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-arc.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-view.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-view-gdk.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-view-aa.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-renderer.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-geometry.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-grid.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-connection.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-attracted.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-attract.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-marshal.h
/usr/include/dia-newcanvas-1.0/dia-newcanvas/dia-canvas-text.h