V. Chvátal and L. Lovász, “Every Directed Graph Has a Semi-Kernel,” Hypergraph Seminar, Lecture Notes in Mathematics, Vol. 441, Springer-Verlag, Berlin, 1974, p. 175.

has been cited by the following article:

• TITLE: Quasi-Kernels for Oriented Paths and Cycles

  AUTHORS: Stephen Bowser, Charles Cable

  KEYWORDS: Digraph; Quasi-Kernel; Path; Cycle

  JOURNAL NAME: Open Journal of Discrete Mathematics, Vol.2 No.2, April 27, 2012

  ABSTRACT: If D is a digraph, then K∈V(D) is a quasi-kernel of D if D［K］is discrete and for each y∈V(D)－K there is x∈K such that the directed distance from y to x is less than three. We give formulae for the number of quasi-kernels and for the number of minimal quasi-kernels of oriented paths and cycles.