@article{MM3_2002_6_1_a13,
     author = {Janez U\v{s}an},
     title = {Note on {Congruence} {Classes} of {n-Groups}},
     journal = {Mathematica Moravica},
     pages = {131 - 135},
     publisher = {mathdoc},
     volume = {6},
     number = {1},
     year = {2002},
     url = {https://geodesic-test.mathdoc.fr/item/MM3_2002_6_1_a13/}
}