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@article{MZM_1991_50_1_a0, author = {M. V. Babich}, title = {Real finite-gap solutions of the equation $\Delta u=\ch u$}, journal = {Matemati\v{c}eskie zametki}, pages = {3--9}, publisher = {mathdoc}, volume = {50}, number = {1}, year = {1991}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1991_50_1_a0/} }
M. V. Babich. Real finite-gap solutions of the equation $\Delta u=\ch u$. Matematičeskie zametki, Tome 50 (1991) no. 1, pp. 3-9. http://geodesic.mathdoc.fr/item/MZM_1991_50_1_a0/