TY  - JOUR
AU  - Simon, Petr
TI  - A closed separable subspace not being a retract of $\beta N$
JO  - Commentationes Mathematicae Universitatis Carolinae
PY  - 1984
SP  - 364
EP  - 365
VL  - 25
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/CMUC_1984__25_2_a17/
LA  - en
ID  - CMUC_1984__25_2_a17
ER  -