@article{10_1090_S0894_0347_02_00409_5,
     author = {Thomas, Simon},
     title = {The classification problem for torsion-free abelian groups of finite rank},
     journal = {Journal of the American Mathematical Society},
     pages = {233--258},
     publisher = {mathdoc},
     volume = {16},
     number = {1},
     year = {2003},
     doi = {10.1090/S0894-0347-02-00409-5},
     url = {http://geodesic.mathdoc.fr/articles/10.1090/S0894-0347-02-00409-5/}
}