TY  - JOUR
AU  - E. I. Timoshenko
TI  - The preservation of elementary and universal equivalence in the
JO  - Algebra i logika
PY  - 1968
SP  - 114
EP  - 119
VL  - 7
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/AL_1968_7_4_a6/
LA  - ru
ID  - AL_1968_7_4_a6
ER  -