@article{IM2_1980_14_2_a2,
     author = {V. I. Danchenko},
     title = {An~integral estimate for the derivative of a~rational function},
     journal = {Izvestiya. Mathematics},
     pages = {257--273},
     year = {1980},
     volume = {14},
     number = {2},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1980_14_2_a2/}
}