@article{10_4064_aa_67_2_123_140,
     author = {Radan Ku\v{c}era},
     title = {Different groups of circular units of a compositum of real quadratic fields},
     journal = {Acta Arithmetica},
     pages = {123--140},
     publisher = {mathdoc},
     volume = {67},
     number = {2},
     year = {1994},
     doi = {10.4064/aa-67-2-123-140},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa-67-2-123-140/}
}