@article{VMUMM_1989_1_a19,
     author = {A. G. Golitsyna},
     title = {A model of sparse scatterers for the {Schr\"odinger} operator on a free group},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {90--92},
     publisher = {mathdoc},
     number = {1},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1989_1_a19/}
}