Let X denote the space of all real, bounded double sequences, and let Φ, φ, Γ be φ-functions. Moreover, let Ψ be an increasing, continuous function for u ≥ 0 such that Ψ(0) = 0.
In this paper we consider some spaces of double sequences provided with two-modular structure given by generalized variations and the translation operator (...).
@article{urn:eudml:doc:41131, title = {Approximation problems in modular spaces of double sequences.}, journal = {Publicacions Matem\`atiques}, volume = {34}, year = {1990}, pages = {259-268}, zbl = {0755.46004}, language = {en}, url = {http://dml.mathdoc.fr/item/urn:eudml:doc:41131} }
Waszak, Aleksander. Approximation problems in modular spaces of double sequences.. Publicacions Matemàtiques, Tome 34 (1990) pp. 259-268. http://gdmltest.u-ga.fr/item/urn:eudml:doc:41131/