@article{1183741695, author = {Welch, Lawrence V.}, title = {A Hierarchy of Families of Recursively Enumerable Degrees}, journal = {J. Symbolic Logic}, volume = {49}, number = {1}, year = {1984}, pages = { 1160-1170}, language = {en}, url = {http://dml.mathdoc.fr/item/1183741695} }
Welch, Lawrence V. A Hierarchy of Families of Recursively Enumerable Degrees. J. Symbolic Logic, Tome 49 (1984) no. 1, pp. 1160-1170. http://gdmltest.u-ga.fr/item/1183741695/