@article{AUPO_1976__15_1_a2,
     author = {Jachanov\'a, Jaroslava and \v{Z}\'akov\'a, Helena},
     title = {On a dependence between polarities and an order of a projective plane},
     journal = {Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica},
     pages = {29--33},
     publisher = {mathdoc},
     volume = {15},
     number = {1},
     year = {1976},
     mrnumber = {0640740},
     zbl = {0371.50013},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AUPO_1976__15_1_a2/}
}