@article{TIMM_2012_18_3_a28,
     author = {M. Yu. Khachai and M. I. Poberii},
     title = {The computational complexity and approximability of a~series of geometric covering problems},
     journal = {Trudy Instituta matematiki i mehaniki},
     pages = {247--260},
     year = {2012},
     volume = {18},
     number = {3},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TIMM_2012_18_3_a28/}
}