It is proved that a separable Fréchet space is quasinormable if, and only if, every quotient space satisfies the density condition of Heinrich. This answers positively a conjecture of Bonet and Dí az in the class of separable Fréchet spaces.
@article{bwmeta1.element.bwnjournal-article-smv125i2p131bwm,
author = {Angela Albanese},
title = {The density condition in quotients of quasinormable Fr\'echet spaces},
journal = {Studia Mathematica},
volume = {122},
year = {1997},
pages = {131-141},
zbl = {0912.46001},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-smv125i2p131bwm}
}
Albanese, Angela. The density condition in quotients of quasinormable Fréchet spaces. Studia Mathematica, Tome 122 (1997) pp. 131-141. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-smv125i2p131bwm/
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