@article{ZNSL_2007_347_a2,
     author = {N. M. Bogolyubov},
     title = {Four-vertex model},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {34--55},
     publisher = {mathdoc},
     volume = {347},
     year = {2007},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2007_347_a2/}
}