%0 Journal Article %T On n-coherent rings, n-hereditary rings and n-regular rings %J Bulletin of the Iranian Mathematical Society %I Iranian Mathematical Society (IMS) %Z 1017-060X %A Zhu, Z. %D 2011 %\ 12/15/2011 %V 37 %N No. 4 %P 251-267 %! On n-coherent rings, n-hereditary rings and n-regular rings %K (n %K 0)-injective modules %K 0)-flat modules %K n-coherent rings %K n-hereditary rings n-regular rings %R %X We observe some new characterizations of $n$-presented modules. Using the concepts of $(n,0)$-injectivity and $(n,0)$-flatness of modules, we also present some characterizations of right $n$-coherent rings, right $n$-hereditary rings, and right $n$-regular rings. %U http://bims.iranjournals.ir/article_384_125e070a2fa775c36ec3c76ac7b10025.pdf