@article{TIMM_2012_18_2_a4,
     author = {R. R. Gadyl'shin and E. A. Shishkina},
     title = {On {Friedrichs} inequalities for a~disk},
     journal = {Trudy Instituta matematiki i mehaniki},
     pages = {48--61},
     year = {2012},
     volume = {18},
     number = {2},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TIMM_2012_18_2_a4/}
}