• John Dauns
  • Yiqiang Zhou
Part of the Trends in Mathematics book series (TM)


This paper is about QI-modules M and the full subcategory σ[M] of Mod-R subgenerated by M. A ring R is a right QI-ring if every quasi-injective right R-module is injective. The module M is QI if all quasi-injective modules in σ[M] are M-injective. Three classes of rings are presented for each of which the QI-modules are precisely the semisimple modules. The QI-modules M are characterized in terms of properties of some lattices of classes of modules in σ[M].


Direct Summand Module Class Subdirect Product Natural Class Boolean Lattice 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Birkhäuser Verlag Basel/Switzerland 2008

Authors and Affiliations

  • John Dauns
    • 1
  • Yiqiang Zhou
    • 2
  1. 1.Tulane UniversityNew OrleansUSA
  2. 2.Memorial University of NewfoundlandSt.John’sCanada

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