@article{FPM_2010_16_1_a13,
     author = {G. S. Sharov and A. E. Milovidov},
     title = {String world surfaces in spaces with compact factor-manifolds},
     journal = {Fundamentalʹna\^a i prikladna\^a matematika},
     pages = {171--177},
     publisher = {mathdoc},
     volume = {16},
     number = {1},
     year = {2010},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FPM_2010_16_1_a13/}
}