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@article{AL_2000_39_5_a2, author = {I. Sh. Kalimullin}, title = {Relative complements in $\Delta_2^0$-degrees with respect to enumerability}, journal = {Algebra i logika}, pages = {547--566}, publisher = {mathdoc}, volume = {39}, number = {5}, year = {2000}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/AL_2000_39_5_a2/} }
I. Sh. Kalimullin. Relative complements in $\Delta_2^0$-degrees with respect to enumerability. Algebra i logika, Tome 39 (2000) no. 5, pp. 547-566. http://geodesic.mathdoc.fr/item/AL_2000_39_5_a2/