@article{10_4064_aa_46_1_57_72,
     author = {Kenneth Williams and Kenneth Hardy},
     title = {A congruence for the index of a unit of a real abelian number field},
     journal = {Acta Arithmetica},
     pages = {57--72},
     publisher = {mathdoc},
     volume = {46},
     number = {1},
     year = {1985},
     doi = {10.4064/aa-46-1-57-72},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa-46-1-57-72/}
}