@article{DAN_1975_225_1_a17,
     author = {V. A. Zagrebnov and I. G. Brankov and N. S. Tonchev},
     title = {A rigorous result on systems that interact with a boson field},
     journal = {Doklady Akademii Nauk},
     pages = {71--73},
     publisher = {mathdoc},
     volume = {225},
     number = {1},
     year = {1975},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1975_225_1_a17/}
}