@article{oai:repository.dl.itc.u-tokyo.ac.jp:00037902, author = {Takagi, T.}, journal = {The journal of the College of Science, Imperial University of Tokyo, Japan = 東京帝國大學紀要. 理科}, month = {May}, pages = {1--42}, title = {Ueber die im Bereiche der rationalen complexen Zahlen Abel'schen Zahlkorper}, volume = {19}, year = {1903} }