Algebra
Colloquium
Volume 11 • Number 4 • December 2004
Central Group Gradings of Incidence Algebras
M.M. Parmenter, E. Spiegel 421 Semisimple Corings
L. El Kaoutit, J. Gomez-Torrecillas, F.J. Lobillo 427 On the Number of Generators of Prime Ideals in Affine Algebras A.S. Sivatski 443 A Note on Bosonization
J.N. Alonso Alvarez, J.M. Fernandez Vilaboa,
R. Gonzalez Rodriguez 451 Local Homology and Local Cohomology
Z.M. Tang 467 On Some Finite Orders of Certain Cyclically Presented Groups
Y.Kim, S.H.Kim 477 Quantum Group Structure Associated to the Quantum Affine
Space
N.H.Hu 483 New Direct Product Rings, Their Structures and Applications
Y.H.Xu, K.P. Shum 493 A Combinatorial Approach to Relative Invariants Associated
with Ar-Type Quivers
M.Nagura 515 Rigid Right Bass Rings
O.D. Artemovych 527 Rings Without Identity Which Are Morita Equivalent to Regular
Rings
P. Ara 533 Contents of Volume 11 541 Author Index for Volume 11 543