@article{ADM_2004_2_a6,
     author = {Selami Ercan},
     title = {Torsion-free groups with every proper homomorphic image an $\bf N_{1}$-group},
     journal = {Algebra and discrete mathematics},
     pages = {56--58},
     publisher = {mathdoc},
     number = {2},
     year = {2004},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ADM_2004_2_a6/}
}