TY  - JOUR
AU  - A. A. Mal'tsev
TI  - On the structure of families of immune, hyperimmune and hyperhyperimmune sets
JO  - Sbornik. Mathematics
PY  - 1985
SP  - 301
EP  - 313
VL  - 52
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/SM_1985_52_2_a1/
LA  - en
ID  - SM_1985_52_2_a1
ER  -