@article{TMF_1990_85_2_a8,
     author = {S. I. Vakaru and M. I. Vladimir and V. A. Moskalenko},
     title = {Diagram technique for the {Hubbard} model.},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {248--257},
     year = {1990},
     volume = {85},
     number = {2},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_1990_85_2_a8/}
}