@article{MZ_1969__111_171185,
     author = {B. Kuttner and B. Thorpe},
     title = {On the {Strong} {N\"orlund} {Summability} of a {Cauchy} {Product} {Series.}},
     journal = {Mathematische Zeitschrift},
     pages = {69--86},
     publisher = {mathdoc},
     volume = {111},
     year = {1969},
     zbl = {0176.01502},
     url = {http://geodesic.mathdoc.fr/item/MZ_1969__111_171185/}
}