digraph stateMachine {
  rankdir=LR;
  node [shape=circle, style=filled, fillcolor=lightgray];

  start [shape=point, label=""];
  FULFILLED [shape=circle, fillcolor=lightgray];
  PAID1 [shape=circle, fillcolor=lightgray];
  PAID3 [shape=circle, fillcolor=lightgray];
  PAID2 [shape=circle, fillcolor=lightgray];
  HAPPEN [shape=circle, fillcolor=lightgray];
  CANCELED [shape=circle, fillcolor=lightgray];
  PAID [shape=circle, fillcolor=lightgray];
  SUBMITTED [shape=circle, fillcolor=lightgray];

  PAID_choice [shape=diamond, label="", fillcolor=lightyellow];
  SUBMITTED_choice [shape=diamond, label="", fillcolor=lightyellow];

  start -> SUBMITTED;

  PAID -> PAID_choice;
  SUBMITTED -> SUBMITTED_choice;

  SUBMITTED -> PAID [label="PAY"];
  PAID -> FULFILLED [label="FULFILL"];
  SUBMITTED -> CANCELED [label="CANCEL [lambda]"];
  PAID -> CANCELED [label="CANCEL"];
  SUBMITTED -> SUBMITTED [label="ABCD"];
  SUBMITTED_choice -> PAID2 [label=" [lambda]"];
  SUBMITTED_choice -> PAID3;
  PAID_choice -> PAID1 [label=" [lambda]"];
  PAID_choice -> PAID2 [label=" [lambda]"];
  PAID_choice -> HAPPEN [label=" [lambda]"];
  PAID_choice -> PAID3;
  PAID2 -> CANCELED;
  PAID3 -> CANCELED;
  PAID1 -> PAID1 [label="ABCD"];
}