TY  - JOUR
AU  - Pondělíček, Bedřich
TI  - On tolerances on periodic semigroups
JO  - Czechoslovak Mathematical Journal
PY  - 1978
SP  - 647
EP  - 649
VL  - 28
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1978.101565/
DO  - 10.21136/CMJ.1978.101565
LA  - en
ID  - 10_21136_CMJ_1978_101565
ER  -