(1.Department of Mathematics,Chaohu College,Hefei 238000,China;2.School of Mathematics and Computer Science,Jishou University,Jishou 416000,Hunan China;3.School of Mathematics,Hunan Institute of Science and Technology,Yueyang 414000,Hunan China)
[1] CHIN W,KLEINER M,QUINN D.Almost Split Sequence for Comodules [J].J. Algebra,2002,249:1-19.[2] TAKEUCHI M.Morita Theorems for Categories of Comodules [J].J. Fac. Sci. Univ. Tokyo,1977,24:629-644.[3] CUADRA J,TORRECILLAS G J.Idemoptents and Morita-Takeuchi Theory [J].Comm. in Algebra,2002,30(5):〖KG*2〗2 405-2 426.[4] LIN I-P.Semiperfect Coalgebra [J].J. Algebra,1977,49:357-373.[5] ASSEM I,SIMSON D,SKOWRONSKI A.Elements of the Representation Theory of Associative Algebras [M]//Techniques of Representation Theory.London Mathematical Society Student Texts 65,2006.