@article{1183732765,
author = {Friedberg, Richard},
title = {A Criterion for Completeness of Degrees of Unsolvability},
journal = {J. Symbolic Logic},
volume = {22},
number = {1},
year = {1957},
pages = { 159-160},
language = {en},
url = {http://dml.mathdoc.fr/item/1183732765}
}
Friedberg, Richard. A Criterion for Completeness of Degrees of Unsolvability. J. Symbolic Logic, Tome 22 (1957) no. 1, pp. 159-160. http://gdmltest.u-ga.fr/item/1183732765/