• Cho, Yong-Uk (Department of Mathematical Education, College of Education, Silla University)
  • Published : 2006.08.01


The purpose of this paper is to describe some characterizations on rational and f-rational extensions of modules, to determine the forms of f-rational extensions of given f-torsion free module for a left exact radical t and investigate the maximal t-rational extensions of modules.


rational extensions;essential extensions;t-rational extensions;t-essential extensions;t-torsion and t-torsion free modules


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