@article{1031710532, author = {Harary, Frank}, title = {On local balance and $N$-balance in signed graphs.}, journal = {Michigan Math. J.}, volume = {3}, number = {2}, year = {1955}, pages = { 37-41}, language = {en}, url = {http://dml.mathdoc.fr/item/1031710532} }
Harary, Frank. On local balance and $N$-balance in signed graphs.. Michigan Math. J., Tome 3 (1955) no. 2, pp. 37-41. http://gdmltest.u-ga.fr/item/1031710532/