@article{PORMA_1999__56_3_48412,
     author = {Sulaiman, W.T.},
     title = {Characterization for relations on some summability methods.},
     journal = {Portugaliae mathematica},
     pages = {273--280},
     publisher = {mathdoc},
     volume = {56},
     number = {3},
     year = {1999},
     zbl = {0937.40005},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_1999__56_3_48412/}
}