@article{ZNSL_2002_293_a2,
     author = {D. Yu. Grigor'ev and I. N. Ponomarenko},
     title = {On non-abelian homomorphic public-key cryptosystems},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {39--58},
     publisher = {mathdoc},
     volume = {293},
     year = {2002},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2002_293_a2/}
}