1. Complex chromatic number of graphs and signed graphs, joint work Lan Anh Pham and with Weiqiang Yu.
  2. Packing signature in signed graphs, joint work with Weiqiang Yu.
  3. Bounding signed bipartite partial t-trees.
  4. Walk power of $K_4$ minor free graphs, joint work with W. He and Q. Sun.
  5. Odd-Hadwiger conjecture for complement of Kneser graphs, joint work with M. Chen and S. Zhou.
  6. Bounding odd-K_4 free signed bipartite graphs, joint work with: M. Petrusevski, R. Skrekovski and Q. Sun.
  7. Powers of graphs, joint work with: D. Auger, Y. Bai, C. Delorme, P. Lebodic, B. Robillard.