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@article{IM2_1995_59_1_a3, author = {Ya. Sh. Il'yasov}, title = {On periodic non-trivial solutions of the equation $-\Delta u=g(u)$ in~$\mathbb R^{N+1}$}, journal = {Izvestiya. Mathematics }, pages = {101--119}, publisher = {mathdoc}, volume = {59}, number = {1}, year = {1995}, language = {en}, url = {http://geodesic.mathdoc.fr/item/IM2_1995_59_1_a3/} }
Ya. Sh. Il'yasov. On periodic non-trivial solutions of the equation $-\Delta u=g(u)$ in~$\mathbb R^{N+1}$. Izvestiya. Mathematics , Tome 59 (1995) no. 1, pp. 101-119. http://geodesic.mathdoc.fr/item/IM2_1995_59_1_a3/