@article{bdj-cpr-10
, author = {Sergey Bereg and Adrian Dumitrescu and Minghui Jiang}
, title = {On covering problems of {R}ado}
, journal = {Algorithmica}
, year = {2010}
, volume = {57}
, number = {3}
, pages = {538--561}
, url = {http://dx.doi.org/10.1007/s00453-009-9298-z}
}