@article{ZNSL_1974_42_a5,
     author = {N. S. Grigor'ev},
     title = {The {Ursell} {Method} for apriori {Estimation} of the {Solution} of the {Neumann} {Problem} for the {Helmholtz} {Equation}},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {85--154},
     publisher = {mathdoc},
     volume = {42},
     year = {1974},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1974_42_a5/}
}