@article{10_4064_cm_15_1_1_9,
     author = {K. Urbanik},
     title = {Remarks on symmetrical operations},
     journal = {Colloquium Mathematicum},
     pages = {1--9},
     publisher = {mathdoc},
     volume = {15},
     number = {1},
     year = {1966},
     doi = {10.4064/cm-15-1-1-9},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm-15-1-1-9/}
}