TY  - JOUR
AU  - Chajda, Ivan
TI  - On Grätzer's problem of binary 1-step congruence schemes
JO  - Czechoslovak Mathematical Journal
PY  - 1989
SP  - 470
EP  - 476
VL  - 39
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1989.102318/
DO  - 10.21136/CMJ.1989.102318
LA  - en
ID  - 10_21136_CMJ_1989_102318
ER  -