1. J. J. Rotman, An introduction to homological algebra.Academic Press, New York, 1979.
2. S. M. Bhatwadekar, On the global dimension of some filtered algebras.J. London Math. Soc. 209(1970), 65–85.
3. K. R. Goodearl, On the global dimension of residue rings II.Trans. Amer. Math. Soc. 209(1970), 65–85.
4. K. R. Goodearl, Global dimension of differential operator rings IV-simple modules.Forum Math. 1(1989), 185–200.
5. J. Koker, Global dimension of rings with Krull dimension.Comm. Algebra 10(1992), 2863–2876.