TY  - JOUR
AU  - Grätzer, G.
AU  - Wenzel, G. H.
TI  - Tolerances, covering systems, and the axiom of choice
JO  - Archivum mathematicum
PY  - 1989
SP  - 27
EP  - 34
VL  - 25
IS  - 1-2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/ARM_1989__25_1-2_a4/
LA  - en
ID  - ARM_1989__25_1-2_a4
ER  -