@article{DAN_1967_173_2_a15,
     author = {D. Ya. Petrina},
     title = {Completeness of perturbation theory amplitudes in amplitude space},
     journal = {Doklady Akademii Nauk},
     pages = {295--297},
     publisher = {mathdoc},
     volume = {173},
     number = {2},
     year = {1967},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1967_173_2_a15/}
}