@article{PIM_1999_N_S_65_79_a10,
     author = {Vladimir Rako\v{c}evi\'c},
     title = {A {Note} on two {Indices} of {Semigroup} {Elements}},
     journal = {Publications de l'Institut Math\'ematique},
     pages = {109 },
     publisher = {mathdoc},
     volume = {_N_S_65},
     number = {79},
     year = {1999},
     zbl = {0947.20041},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PIM_1999_N_S_65_79_a10/}
}