@article{TIMM_2015_21_4_a8,
     author = {V. I. Berdyshev},
     title = {A moving object and observers in $\mathbb R^2$ with piecewise smooth shading set},
     journal = {Trudy Instituta matematiki i mehaniki},
     pages = {95--101},
     publisher = {mathdoc},
     volume = {21},
     number = {4},
     year = {2015},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TIMM_2015_21_4_a8/}
}