**Conjecture**Every oriented graph with minimum outdegree contains a directed path of length .

In fact, Thomassé made the following stronger conjecture which implies the celebrated Cacetta-Häggkvist Conjecture.

**Conjecture**Every digraph with minimum outdegree and directed girth , contains a directed path of length .

This conjecture holds easily when . For it is the above conjecture which is still open.

## Bibliography

*[S] Blair D. Sullivan: A Summary of Problems and Results related to the Caccetta-Haggkvist Conjecture

* indicates original appearance(s) of problem.