@article{AUPO_1971__11_1_a2,
     author = {Jachanov\'a, Jaroslava},
     title = {On permutable quadratic inversions in plane with two common singular points},
     journal = {Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica},
     pages = {29--36},
     publisher = {mathdoc},
     volume = {11},
     number = {1},
     year = {1971},
     mrnumber = {0333943},
     zbl = {0272.50016},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AUPO_1971__11_1_a2/}
}