@article{ZNSL_1987_160_a11,
     author = {G. V. Kuz'mina},
     title = {Extremal properties of quadratic differentials with trajectories which are asymptotically similar to logarithmic spirals},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {121--137},
     publisher = {mathdoc},
     volume = {160},
     year = {1987},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1987_160_a11/}
}