@article{FPM_1995_1_4_a12,
     author = {I. Kh. Sabitov},
     title = {Some remarks on the tubes of negative curvature},
     journal = {Fundamentalʹna\^a i prikladna\^a matematika},
     pages = {1033--1043},
     publisher = {mathdoc},
     volume = {1},
     number = {4},
     year = {1995},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FPM_1995_1_4_a12/}
}