@article{MT_2001_4_1_a1, author = {Yu. L. Ershov}, title = {Separable {Conservativity}}, journal = {Matemati\v{c}eskie trudy}, pages = {18--24}, publisher = {mathdoc}, volume = {4}, number = {1}, year = {2001}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MT_2001_4_1_a1/} }