@article{DCG_1995__13_3-4_131373,
     author = {Fejes G. T\'oth},
     title = {Covering the {Plane} with {Two} {Kinds} of {Circles.}},
     journal = {Discrete & computational geometry},
     pages = {445--458},
     publisher = {mathdoc},
     volume = {13},
     number = {3-4},
     year = {1995},
     zbl = {0830.52009},
     url = {http://geodesic.mathdoc.fr/item/DCG_1995__13_3-4_131373/}
}