@article{DAN_1979_246_3_a4,
     author = {I. Jo and N. La\v{z}eti\'c},
     title = {Derivatives of partial sums of spectral decompositions corresponding to nonnegative selfadjoint extensions of {Sturm--Liouville} operators},
     journal = {Doklady Akademii Nauk},
     pages = {534--536},
     publisher = {mathdoc},
     volume = {246},
     number = {3},
     year = {1979},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1979_246_3_a4/}
}