@article{ZNSL_1978_78_a5,
     author = {A. P. Katchalov},
     title = {Behavior of the roots of the equation $w'_1(z)+\sigma w_1(z)=0$},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {90--94},
     publisher = {mathdoc},
     volume = {78},
     year = {1978},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1978_78_a5/}
}