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@article{DAN_1963_148_6_a7, author = {S. A. Pak}, title = {Sign-preserving conditions for the {Green's} function of a {Sturm--Liouville} problem}, journal = {Doklady Akademii Nauk}, pages = {1265--1267}, publisher = {mathdoc}, volume = {148}, number = {6}, year = {1963}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1963_148_6_a7/} }
S. A. Pak. Sign-preserving conditions for the Green's function of a Sturm--Liouville problem. Doklady Akademii Nauk, Tome 148 (1963) no. 6, pp. 1265-1267. http://geodesic.mathdoc.fr/item/DAN_1963_148_6_a7/