qt-everywhere-src-5.15.1/qtxmlpatterns/src/xmlpatterns/schema/doc/Notation_diagram.dot

digraph Notation {
  mindist = 2.0
  1 -> 2 [label="annotation"]
  1 [shape=doublecircle, style=filled, color=blue]
  2 [shape=doublecircle, style=filled, color=green]
}