@article{GDZPPN002287544, title = {Computing Degrees of Unsolvability.}, journal = {Mathematische Annalen}, volume = {137}, year = {1959}, pages = {125-140}, zbl = {0086.01101}, url = {http://dml.mathdoc.fr/item/GDZPPN002287544} }
ROGERS, H. Computing Degrees of Unsolvability.. Mathematische Annalen, Tome 137 (1959) pp. 125-140. http://gdmltest.u-ga.fr/item/GDZPPN002287544/