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@article{AL_1979_18_4_a3, author = {G. N. Kobzev}, title = {tt-degrees of recursively enumerable {Turing} {degrees.~II}}, journal = {Algebra i logika}, pages = {415--425}, publisher = {mathdoc}, volume = {18}, number = {4}, year = {1979}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/AL_1979_18_4_a3/} }
G. N. Kobzev. tt-degrees of recursively enumerable Turing degrees.~II. Algebra i logika, Tome 18 (1979) no. 4, pp. 415-425. http://geodesic.mathdoc.fr/item/AL_1979_18_4_a3/