1. Cohomology of Groups;Brown,1982
2. Sur quelques points d'algèbre homologique;Grothendieck;Tohoku Math. J.,1957
3. Cohomology of group extensions;Hochschild;Trans. Am. Math. Soc.,1953
4. Zero divisors and idempotents in group rings;Linnell,1977
5. The Algebraic Structure of Group Rings;Passman,1977