Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DE_1968_4_6_a22, author = {N. N. Ladis}, title = {The absence of bilateral attraction points}, journal = {Differencialʹnye uravneni\^a}, pages = {1157}, publisher = {mathdoc}, volume = {4}, number = {6}, year = {1968}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1968_4_6_a22/} }
N. N. Ladis. The absence of bilateral attraction points. Differencialʹnye uravneniâ, Tome 4 (1968) no. 6. http://geodesic.mathdoc.fr/item/DE_1968_4_6_a22/