TY  - JOUR
AU  - Köbler, Johannes
AU  - Schöning, Uwe
AU  - Wagner, Klaus W.
TI  - The difference and truth-table hierarchies for NP
JO  - RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications
PY  - 1987
SP  - 419
EP  - 435
VL  - 21
IS  - 4
PB  - EDP-Sciences
UR  - http://archive.numdam.org/item/ITA_1987__21_4_419_0/
LA  - en
ID  - ITA_1987__21_4_419_0
ER  -