@article{10_4153_CJM_1967_104_2,
     author = {Bottema, O.},
     title = {The {Inversive} {Distance} {Between} {Two} {Circles}},
     journal = {Canadian journal of mathematics},
     pages = {1149--1152},
     year = {1967},
     volume = {19},
     number = {1},
     doi = {10.4153/CJM-1967-104-2},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1967-104-2/}
}