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@article{DE_1991_27_7_a16, author = {S. I. Piskarev}, title = {Approximation of positive $C_0$-semigroups of operators}, journal = {Differencialʹnye uravneni\^a}, pages = {1245--1250}, publisher = {mathdoc}, volume = {27}, number = {7}, year = {1991}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1991_27_7_a16/} }
S. I. Piskarev. Approximation of positive $C_0$-semigroups of operators. Differencialʹnye uravneniâ, Tome 27 (1991) no. 7, pp. 1245-1250. http://geodesic.mathdoc.fr/item/DE_1991_27_7_a16/