Geodesic
Modules for quadratic extensions of Dedekind rings
Zapiski Nauchnykh Seminarov POMI, Analytical theory of numbers and theory of functions. Part 8, Tome 160 (1987) 
D. K. Faddeev. Modules for quadratic extensions of Dedekind rings. Zapiski Nauchnykh Seminarov POMI, Analytical theory of numbers and theory of functions. Part 8, Tome 160 (1987). http://geodesic.mathdoc.fr/item/ZNSL_1987_160_a25/
@article{ZNSL_1987_160_a25,
     author = {D. K. Faddeev},
     title = {Modules for quadratic extensions of {Dedekind} rings},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {262},
     year = {1987},
     volume = {160},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1987_160_a25/}
}
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Voir la notice du chapitre de livre provenant de la source Math-Net.Ru

Let $\sigma$ be a Dedekind ring, let $Q$ be a maximal order in a quadratic extension $K$ of the field $k$ of quotients of the ring $\sigma$, let $\Lambda$ be a subring of the ring $\sigma$, containing $\sigma$ and such that $\Lambda k=K$. It is proved that $\sigma/\Lambda$is a cyclic $\Lambda$-module. From here there follows, in particular, that each finitely generated torsion-free $\Lambda$-module is a direct sum of modules which are isomorphic to the ideals of ring $\Lambda$.