@article{GDZPPN002536226,
title = {Graph equations, graph inequalities and a fixed point theorem.},
journal = {Publications de l'Institut Math\'ematique [Elektronische Ressource]},
volume = {34},
year = {1976},
pages = {59-66},
zbl = {0344.05160},
language = {en},
url = {http://dml.mathdoc.fr/item/GDZPPN002536226}
}
Lackovic, I.B.; Cvetkovic, D.M. Graph equations, graph inequalities and a fixed point theorem.. Publications de l'Institut Mathématique [Elektronische Ressource], Tome 34 (1976) pp. 59-66. http://gdmltest.u-ga.fr/item/GDZPPN002536226/