@article{MZ_1968__103_170900,
     author = {D. Borwein and F.P. Cass},
     title = {Strong {N\"orlund} {Summability.}},
     journal = {Mathematische Zeitschrift},
     pages = {94--111},
     publisher = {mathdoc},
     volume = {103},
     year = {1968},
     zbl = {0157.38001},
     url = {http://geodesic.mathdoc.fr/item/MZ_1968__103_170900/}
}