3 fontname="Inconsolata, Consolas"
11 node [shape=box, fontname="Inconsolata, Consolas", fontsize=10, penwidth=0.5, style=filled, fillcolor=white]
12 edge [fontname="Inconsolata, Consolas", fontsize=10, penwidth=0.5]
21 Reader -> Writer [style=invis]
35 Handler [label="<<concept>>\nHandler"]
38 edge [arrowtail=onormal, dir=back]
45 edge [arrowhead=vee, style=dashed, constraint=false]
46 Reader -> Handler [label="calls"]
47 Value -> Handler [label="calls"]
48 Document -> Reader [label="uses"]