@article{DE_1980_16_8_a20,
     author = {V. B. Pilyugina},
     title = {Investigation of a system with a triple zero characteristic root},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1520--1522},
     publisher = {mathdoc},
     volume = {16},
     number = {8},
     year = {1980},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1980_16_8_a20/}
}