Consider the following two ways to colour the vertices of a graph where the requirement that
adjacent vertices get distinct colours is relaxed. A colouring has" defect" $ d $ if each …

We prove that for every planar graph X of treedepth h, there exists a positive integer c such
that for every X-minor-free graph G, there exists a graph H of treewidth at most f (h) such that …

Hadwiger's conjecture asserts that every K t‐minor‐free graph has a proper (t− 1)‐colouring.
We relax the conclusion in Hadwiger's conjecture via improper colourings. We prove that …

Product structure of graph classes with bounded treewidth Page 1 Combinatorics, Probability
and Computing (2023), 1–26 doi:10.1017/S0963548323000457 ARTICLE Product structure of …

Clustered 3-colouring graphs of bounded degree Page 1 Combinatorics, Probability and
Computing (2022), 31, pp. 123–135 doi:10.1017/S0963548321000213 ARTICLE Clustered …

This thesis contains a brief overview of my research activities between 2009 and 2017 as
Chargé de Recherche CNRS at the G-SCOP laboratory in Grenoble, France. I chose to …

The clustering of a graph coloring is the maximum size of monochromatic components. This
paper studies colorings with bounded clustering in graph classes with bounded …

We prove that for every graph H, if a graph G has no (odd) H minor, then its vertex set V (G)
can be partitioned into three sets X 1, X 2, X 3 such that for each i, the subgraph induced on …

Recent results show that several important graph classes can be embedded as subgraphs
of strong products of simpler graphs classes (paths, small cliques, or graphs of bounded …

Hajós conjectured that every graph containing no subdivision of the complete graph K s+ 1
is properly s-colorable. This conjecture was disproved by Catlin. Indeed, the maximum …