Claws in digraphs (Q2473004)

A rooted tree is a tree with a specified vertex called the root of the tree. An in-branching is an orientation of a rooted tree in which every vertex except the root has out degree 1. A claw is an in-branching in which only the root may have an in degree more than 2. The paper studies the existence of claws in digraph, thereby extending a result of \textit{M. Saks} and \textit{V. T. Sós} [Colloq. Math. Soc. János Bolyai 37, 663--674 (1984; Zbl 0566.05032)] to the tournament-like digraphs.