Voir la notice de l'article provenant de la source Math-Net.Ru
@article{AL_1977_16_6_a1, author = {Yu. L. Ershov}, title = {Numeration of the class $\mathbb{C}^*_{20}$}, journal = {Algebra i logika}, pages = {637--642}, publisher = {mathdoc}, volume = {16}, number = {6}, year = {1977}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/AL_1977_16_6_a1/} }
Yu. L. Ershov. Numeration of the class $\mathbb{C}^*_{20}$. Algebra i logika, Tome 16 (1977) no. 6, pp. 637-642. http://geodesic.mathdoc.fr/item/AL_1977_16_6_a1/