@article{ZNSL_1974_44_a9,
     author = {N. A. Shirokov},
     title = {On a~generalization of {Ahlfors'} theorem},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {179--185},
     publisher = {mathdoc},
     volume = {44},
     year = {1974},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1974_44_a9/}
}