@article{TMF_1977_32_2_a6,
     author = {I. P. Dzyub and V. A. Nikolaev},
     title = {Method of variational derivatives in the theory of spin waves at low temperatures},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {237--246},
     publisher = {mathdoc},
     volume = {32},
     number = {2},
     year = {1977},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_1977_32_2_a6/}
}