TY  - JOUR
AU  - Schwarz, Friedhelm
TI  - Extensionable topological hulls and topological universe hulls inside the category of pseudotopological spaces
JO  - Commentationes Mathematicae Universitatis Carolinae
PY  - 1990
SP  - 123
EP  - 127
VL  - 31
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/CMUC_1990__31_1_a16/
LA  - en
ID  - CMUC_1990__31_1_a16
ER  -