A shorter direct proof of that result was obtained by Geelen, Gerards, and Whittle [GGW00p]. However, to prove Theorem 7.0.1, the well-quasi-ordering for graphs of bounded tree-width is needed only ...

The Yule tree graph. The Yule tree is a graph with one edge coming in and two edges coming out of each branch-point. The branches represent the time periods between the evolution of new species. If ...