@article{10_4153_CMB_1967_031_1,
     author = {Ustina, F.},
     title = {The {Hausdorff} {Means} for {Double} {Sequences}},
     journal = {Canadian mathematical bulletin},
     pages = {347--352},
     year = {1967},
     volume = {10},
     number = {3},
     doi = {10.4153/CMB-1967-031-1},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1967-031-1/}
}