@article{TMF_1970_2_1_a10,
     author = {Yu. G. Rudoi},
     title = {Bogolyubov's statistical variational principle and the {Green's} function method applied to the {Heisenberg--Ising} model},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {129--148},
     publisher = {mathdoc},
     volume = {2},
     number = {1},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_1970_2_1_a10/}
}