This image was made using a tools called tred and dot, both part of the graphviz package of tools for manipulating and visualizing graphs. First, the dot file Tred-Gprime.dot was created using tred and the dot file for Image:Tred-G.png by issuing the following command:
tred < Tred-G.dot > Tred-Gprime.dot
The result was the following dot file:
digraphg{a->b;a->c;b->d;c->d;d->e;}
The image itself was then created using the following command: