@article{01278753, title = {On the absolute summability of series with respect to block-orthonormal systems.}, journal = {Georgian Mathematical Journal}, volume = {6}, year = {1999}, pages = {83-90}, doi = {10.1023/A:1022982527065}, zbl = {0920.42023}, language = {en}, url = {http://dml.mathdoc.fr/item/01278753} }
Nadibaidze, G. On the absolute summability of series with respect to block-orthonormal systems.. Georgian Mathematical Journal, Tome 6 (1999) pp. 83-90. doi : 10.1023/A:1022982527065. http://gdmltest.u-ga.fr/item/01278753/