@article{1183744184,
author = {Jockusch, Carl G. and Slaman, Theodore A.},
title = {On the $\Sigma\_2$-Theory of the Upper Semilattice of Turing Degrees},
journal = {J. Symbolic Logic},
volume = {58},
number = {1},
year = {1993},
pages = { 193-204},
language = {en},
url = {http://dml.mathdoc.fr/item/1183744184}
}
Jockusch, Carl G.; Slaman, Theodore A. On the $\Sigma_2$-Theory of the Upper Semilattice of Turing Degrees. J. Symbolic Logic, Tome 58 (1993) no. 1, pp. 193-204. http://gdmltest.u-ga.fr/item/1183744184/