1. Andersen, H.H., Lauritzen, N.: Twisted Verma modules. In: Studies in Memory of Issai Schur, Vol. 210, Progress in Math., Birkhäuser, Basel, 2002, pp. 1?26
2. Andersen, H.H., Stroppel, C.: Twisting functors on 0. Represent. Theory 7, 681?699 (2003)
3. Arkhipov, S.: Semi-infinite cohomology of associative algebras and bar duality. Internat. Math. Res. Notices 17, 833?863 (1997)
4. Arkhipov, S.: Algebraic construction of contragradient quasi-Verma modules in positive characteristics. Preprint MPI 2001-34, Max-Planck Institute für Math- ematik, 2001
5. Auslander, M.: Representation theory of Artin algebras I. Commun. Alg. 1, 177?268 (1974)