@article{ZNSL_2009_367_a12,
     author = {M. N. Yakovlev},
     title = {A bound for the error of the {Ritz} method in the case of the {Lidstone} problem for a~singular differential equation of fourth order},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {195--201},
     publisher = {mathdoc},
     volume = {367},
     year = {2009},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2009_367_a12/}
}