1. Bass, Hyman:Algebraic K-Theory. New York (Benjamin), 1968.
2. Benz, Walter: “On Barbilian domains over commutative rings.”J. Geom. 12/2 (1979), 146–151.
3. Bourbaki, Nicolas:Commutative Algebra. Paris (Hermann) and Reading, Massachusetts (Addison-Wesley), 1972.
4. Estes, Dennis, and Jack Ohm: “Stable range in commutative rings.”J. Alg. 7 (1967), 343–362.
5. Jaffard, Paul: “Contributions à la théorie des groupes ordonnés.”J. Math. Pures Appl. 32 (1953), 203–280.