@article{ZNSL_2009_371_a7,
     author = {S. I. Kalmykov},
     title = {On modulus estimate of rational function},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {109--116},
     publisher = {mathdoc},
     volume = {371},
     year = {2009},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2009_371_a7/}
}