@article{DE_1989_25_9_a22,
     author = {A. I. Zeifman},
     title = {Positivity of the {Cauchy} matrix of a linear periodic system},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1618--1619},
     publisher = {mathdoc},
     volume = {25},
     number = {9},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1989_25_9_a22/}
}