In Section 1, we survey the existence theorems tor a kernel; in Section 2, we discuss a new conjecture which could constitute a bridge between the kernel problems and the perfect graph conjecture. In fact, we believe that a graph is 'quasi-perfect' if and only if it is perfect. © 1991, Elsevier Inc. All rights reserved.
Berge, C., & Duchet, P. (1991). Recent Problems and Results about Kernels in Directed Graphs. Annals of Discrete Mathematics, 48(C), 27–31. https://doi.org/10.1016/S0167-5060(08)71035-5