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@misc{AL_1990_29_2_a0, title = {Yuri\u{\i} {Leonidovich} {Ershov} (on the occasion of his fiftieth birthday)}, journal = {Algebra i logika}, pages = {135--138}, publisher = {mathdoc}, volume = {29}, number = {2}, year = {1990}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/AL_1990_29_2_a0/} }
Yuri\u{\i} Leonidovich Ershov (on the occasion of his fiftieth birthday). Algebra i logika, Tome 29 (1990) no. 2, pp. 135-138. http://geodesic.mathdoc.fr/item/AL_1990_29_2_a0/