@article{MZM_1979_26_2_a4,
     author = {G. M. Ustinov},
     title = {Convergence of positive operators},
     journal = {Matemati\v{c}eskie zametki},
     pages = {201--216},
     publisher = {mathdoc},
     volume = {26},
     number = {2},
     year = {1979},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1979_26_2_a4/}
}