Comments on "Computer Generation of Trees and Co-Trees in a Cascade of Multiterminal Networks

The problem of efficient generation of all trees has been considered in the above paper´ by Chen [1]. The method is to decompose the original graph into several components and determining appropriate subgraphs in each component and then combining these subgraphs to obtain the desired results. We show that this method has an undesirable feature, which is the duplicate generation of some trees. Therefore, Theorem 4 of the paper [1] must be corrected. The definitions of all symbols will not be redefined here; we refer to Chen´s original paper for detailed treatment.