@article{SM_2005_196_9_a2,
     author = {E. M. Matveev},
     title = {The index of multiplicative groups of algebraic numbers},
     journal = {Sbornik. Mathematics},
     pages = {1307--1318},
     publisher = {mathdoc},
     volume = {196},
     number = {9},
     year = {2005},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2005_196_9_a2/}
}