@article{10_4064_cm_19_1_9_21,
     author = {J. P{\l}onka},
     title = {On the number of independent elements in finite abstract algebras with two binary symmetrical operations},
     journal = {Colloquium Mathematicum},
     pages = {9--21},
     publisher = {mathdoc},
     volume = {19},
     number = {1},
     year = {1968},
     doi = {10.4064/cm-19-1-9-21},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm-19-1-9-21/}
}