@article{ZNSL_2000_266_a4,
     author = {A. M. Vershik},
     title = {Numerical invariants of exponential groups and locally free approximation of the braid group},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {51--63},
     year = {2000},
     volume = {266},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2000_266_a4/}
}