1 digraph SimpleContent {

     2   mindist = 2.0

     3   1 -> 3 [label="restriction"]

     4   1 -> 2 [label="annotation"]

     5   1 -> 3 [label="extension"]

     6   2 -> 3 [label="restriction"]

     7   2 -> 3 [label="extension"]

     8   1 [shape=circle, style=filled, color=blue]

     9   2 [shape=circle, style=filled, color=red]

    10   3 [shape=doublecircle, style=filled, color=green]

    11 }