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@article{MS_1956__80_3_a2, author = {{\CYRA}.{\CYRI}. {\CYRF}{\cyre}{\cyrt} and {\CYRL}.{\CYRB}. {\CYRB}{\cyro}{\cyrd}{\cyrr}{\cyre}{\cyrc}{\cyro}{\cyrv}{\cyra}}, title = {{\CYRF}{\cyru}{\cyrn}{\cyrk}{\cyrc}{\cyri}{\cyri} {\cyrs} {\cyrp}{\cyrr}{\cyro}{\cyrs}{\cyrt}{\cyrery}{\cyrm}{\cyri} {\cyrl}{\cyri}{\cyrn}{\cyri}{\cyrya}{\cyrm}{\cyri} {\cyru}{\cyrr}{\cyro}{\cyrv}{\cyrn}{\cyrya}}, journal = {Matemati\v{c}eskij sbornik}, pages = {303--318}, publisher = {mathdoc}, volume = {80}, number = {3}, year = {1956}, zbl = {0074.04302}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MS_1956__80_3_a2/} }
А.И. Фет; Л.Б. Бодрецова. Функции с простыми линиями уровня. Matematičeskij sbornik, Tome 80 (1956) no. 3, pp. 303-318. http://geodesic.mathdoc.fr/item/MS_1956__80_3_a2/