1. Maximum induced forests of planar graphs;Akiyama;Graphs Combin.,1987
2. A conjecture on planar graphs;Albertson,1979
3. M. Albertson, R. Haas, A problem raised at the DIMACS Graph Coloring Week, New Jersey, 1998.
4. A proof of Grünbaum’s conjecture on the acyclic 5-colorability of planar graphs;Borodin;Dokl. Akad. Nauk SSSR,1976
5. Maximum induced forests in graphs of bounded treewidth;Chappell;Electron. J. Combin.,2013