digraph
| Title | Source | Status | Imp. | Posted |
|---|---|---|---|---|
| Monochromatic reachability or rainbow triangles | opg | partial | ★★★ | 2008-07-15 |
| Non-edges vs. feedback edge sets in digraphs | opg | partial | ★★★ | 2008-07-08 |
| Universal highly arc transitive digraphs | opg | solved | ★★★ | 2007-10-21 |
| Woodall's Conjecture | opg | partial | ★★★ | 2007-04-05 |
| Highly arc transitive two ended digraphs | opg | disproved | ★★ | 2007-10-29 |
| The Two Color Conjecture | opg | partial | ★★ | 2007-03-26 |