The algorithm of Plotkin et al. takes time O(mn/d), where m is the number of edges in the input. Wulff-Nilsen (2011) improved this for non-sparse graphs to O(m + n2 + ε/d). Wulff-Nilsen, Christian (2011), "Separator Theorems for Minor-Free and Shallow Minor-Free Graphs with Applications", Proc. 52nd IEEE Symp. Foundations of Computer Science (FOCS), pp. 37–46, arXiv:1107.1292, doi:10.1109/FOCS.2011.15, ISBN978-0-7695-4571-4.
The algorithm of Plotkin et al. takes time O(mn/d), where m is the number of edges in the input. Wulff-Nilsen (2011) improved this for non-sparse graphs to O(m + n2 + ε/d). Wulff-Nilsen, Christian (2011), "Separator Theorems for Minor-Free and Shallow Minor-Free Graphs with Applications", Proc. 52nd IEEE Symp. Foundations of Computer Science (FOCS), pp. 37–46, arXiv:1107.1292, doi:10.1109/FOCS.2011.15, ISBN978-0-7695-4571-4.