@article{02099340,
title = {On upper and lower weakly },
journal = {Novi Sad Journal of Mathematics},
volume = {32},
year = {2002},
pages = {7-24},
zbl = {1050.54014},
language = {en},
url = {http://dml.mathdoc.fr/item/02099340}
}
Popa, Valeriu; Noiri, Takashi. On upper and lower weakly . Novi Sad Journal of Mathematics, Tome 32 (2002) pp. 7-24. http://gdmltest.u-ga.fr/item/02099340/