@article{GDZPPN002196182,
title = {Divisibility of class numbers of real cyclic extensions of degree 4 over Q.},
journal = {Journal f\"ur die reine und angewandte Mathematik},
volume = {310},
year = {1979},
pages = {365-372},
zbl = {0395.12013},
url = {http://dml.mathdoc.fr/item/GDZPPN002196182}
}
Kobayashi, Shinju. Divisibility of class numbers of real cyclic extensions of degree 4 over Q.. Journal für die reine und angewandte Mathematik, Tome 310 (1979) pp. 365-372. http://gdmltest.u-ga.fr/item/GDZPPN002196182/