Gutman, I.; Estrada, E.; Ivanciuc, O. Some Properties of the Wiener Polynomial of Trees. Graph Theory Notes. New York XXXVI, 1999, 7-13.

Gutman, I.; Estrada, E.; Ivanciuc, O. Some Properties of the Wiener Polynomial of Trees. Graph Theory Notes. New York XXXVI, 1999, 7-13.