@article{1259943863, author = {HIROSE, Ken}, title = {An investigation on degrees of unsolvability}, journal = {J. Math. Soc. Japan}, volume = {20}, number = {4}, year = {1968}, pages = { 609-633}, language = {en}, url = {http://dml.mathdoc.fr/item/1259943863} }
HIROSE, Ken. An investigation on degrees of unsolvability. J. Math. Soc. Japan, Tome 20 (1968) no. 4, pp. 609-633. http://gdmltest.u-ga.fr/item/1259943863/