@article{MM3_2010_14_1_a5,
     author = {Radoslav Gali\'c and Anita Kati\'c},
     title = {Central {Operation} of the {(n,m)-Group}},
     journal = {Mathematica Moravica},
     pages = {53 - 59},
     publisher = {mathdoc},
     volume = {14},
     number = {1},
     year = {2010},
     url = {https://geodesic-test.mathdoc.fr/item/MM3_2010_14_1_a5/}
}