TY  - JOUR
AU  - Li, Jinjin
AU  - Lin, Shou
TI  - $k$-systems, $k$-networks and $k$-covers
JO  - Czechoslovak Mathematical Journal
PY  - 2006
SP  - 239
EP  - 245
VL  - 56
IS  - 1
PB  - mathdoc
UR  - https://geodesic-test.mathdoc.fr/item/CMJ_2006__56_1_a13/
LA  - en
ID  - CMJ_2006__56_1_a13
ER  -