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@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/} }
A. I. Zeifman. Positivity of the Cauchy matrix of a linear periodic system. Differencialʹnye uravneniâ, Tome 25 (1989) no. 9, pp. 1618-1619. http://geodesic.mathdoc.fr/item/DE_1989_25_9_a22/