@article{PORMA_2006__63_3_55299,
     author = {Luca, Florian and St\u{a}nic\u{a}, Pantelimon},
     title = {.},
     journal = {Portugaliae mathematica},
     pages = {251--260},
     publisher = {mathdoc},
     volume = {63},
     number = {3},
     year = {2006},
     zbl = {1160.11009},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_2006__63_3_55299/}
}