@article{JRAM_1992__426_153408,
     author = {Jorge Morales},
     title = {On some invariants for systems of quadratic forms over the integers.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {107--116},
     year = {1992},
     volume = {426},
     zbl = {0737.11006},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1992__426_153408/}
}