Completely independent spanning trees in the underlying graph of a line digraph (Q5936061)

Trees \(T_1,\dots,T_k\) are completely independent spanning trees in a graph \(H\), if for any vertex \(r\) in \(H\) they are independent spanning trees rooted at \(r\). The paper gives a characterization of completely independent spanning trees. Further, it is shown that for any \(k\)-vertex-connected line digraph \(L(G)\), there are \(k\) completely independent spanning trees in the underlying graph of \(L(G)\).