@article{10_4064_aa_67_3_229_239,
     author = {Jin Nakagawa},
     title = {Orders of quadratic extensions of number fields},
     journal = {Acta Arithmetica},
     pages = {229--239},
     publisher = {mathdoc},
     volume = {67},
     number = {3},
     year = {1994},
     doi = {10.4064/aa-67-3-229-239},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa-67-3-229-239/}
}