TY  - JOUR
AU  - Michel, Horst
TI  - Generation of operation-invariant classes of sets
JO  - Mathematica slovaca
PY  - 1983
SP  - 257
EP  - 268
VL  - 33
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MASLO_1983__33_3_a2/
LA  - en
ID  - MASLO_1983__33_3_a2
ER  -