Kernels in graphs with a clique-cutset. - Henry Jacob (Discret. Math., 1996)

About quasi-kernels in a digraph. - Henry Jacob; Henry Meyniel (Discret. Math., 1996)

Some operations preserving the existence of kernels. - Mostafa Blidia; Pierre Duchet; Henry Jacob; Frédéric Maffray; Henry Meyniel (Discret. Math., 1999)