1. Linear Systems over Commutative Rings;Brewer,1986
2. Dynamic feedback over commutative rings;Brewer;Linear Algebra Appl.,1988
3. Remarks on the pole-shifting problem over rings;Bumby;J. Pure Appl. Algebra,1981
4. W. Schmale, A geometric approach to dynamic feedback cyclization over commutative rings, Preprint.
5. Linear systems over commutative rings: A survey;Sontag;Richerche Automat.,1976