@article{UFA_2017_9_2_a4,
     author = {B. A. Klishchuk and R. R. Salimov},
     title = {Lower bounds for the area of the image of a circle},
     journal = {Ufa mathematical journal},
     pages = {55--61},
     year = {2017},
     volume = {9},
     number = {2},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/UFA_2017_9_2_a4/}
}