TY  - JOUR
AU  - J. Mohrherr
TI  - A conjecture of Ershov for a relative hierarchy fails near $\mathcal{O}$
JO  - Algebra i logika
PY  - 1983
SP  - 232
EP  - 235
VL  - 22
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/AL_1983_22_2_a9/
LA  - en
ID  - AL_1983_22_2_a9
ER  -