@article{GDZPPN002197898,
title = {Signatures of units and congruences (mod 4) in certain real quadratic fields. II.},
journal = {Journal f\"ur die reine und angewandte Mathematik},
volume = {316},
year = {1980},
pages = {115-126},
zbl = {0439.12004},
url = {http://dml.mathdoc.fr/item/GDZPPN002197898}
}
Lagarias, J.C. Signatures of units and congruences (mod 4) in certain real quadratic fields. II.. Journal für die reine und angewandte Mathematik, Tome 316 (1980) pp. 115-126. http://gdmltest.u-ga.fr/item/GDZPPN002197898/