@article{2273, author = {Wintner, Aurel}, title = {On an instability criterion of Liapounoff}, journal = {Portugaliae mathematica}, volume = {15}, year = {1956}, pages = {13-18}, zbl = {0071.30802}, mrnumber = {0082019}, language = {en}, url = {http://dml.mathdoc.fr/item/2273} }
Wintner, Aurel. On an instability criterion of Liapounoff. Portugaliae mathematica, Tome 15 (1956) pp. 13-18. http://gdmltest.u-ga.fr/item/2273/