@article{GFA_1995__5_4_58197,
     author = {G. Perelman},
     title = {Widths of {Nonnegatively} {Curved} {Spaces.}},
     journal = {Geometric and functional analysis},
     pages = {445--463},
     publisher = {mathdoc},
     volume = {5},
     number = {4},
     year = {1995},
     zbl = {0845.53031},
     url = {http://geodesic.mathdoc.fr/item/GFA_1995__5_4_58197/}
}