@article{FAA_1992_26_1_a2,
     author = {S. M. Natanzon},
     title = {Differential equations on the {Prym} theta function. a realness criterion for two-dimensional, finite-zone, potential {Schr\"odinger} operators},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {17--26},
     publisher = {mathdoc},
     volume = {26},
     number = {1},
     year = {1992},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1992_26_1_a2/}
}