TY  - JOUR
AU  - Jakubík, Ján
TI  - Quasiorder on Systems of Directed Sets
JO  - Mathematica slovaca
PY  - 1974
SP  - 173
EP  - 177
VL  - 24
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MASLO_1974__24_2_a7/
LA  - en
ID  - MASLO_1974__24_2_a7
ER  -