Graph Nodes:
X10;X13;X2;X8;X9;X11;X1;X6;X3;X7

Graph Edges:
1. X10 <-> X8
2. X10 <-> X9
3. X13 o-> X2
4. X2 <-> X8
5. X2 --> X1
6. X2 --> X7
7. X8 <-> X6
8. X8 <-> X3
9. X9 --> X11
10. X1 o-> X9
11. X11 <-> X6
12. X11 <-> X3
13. X7 o-> X11
