@article{IVM_1977_4_a5,
     author = {B. A. Kats},
     title = {Convexity and starlikeness of the level curves of rational {functions.~II}},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {44--52},
     year = {1977},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1977_4_a5/}
}