1. See e.g. Adler, S.: In: Lectures on elementary particles and quantum field theory, Deser, S. et al. (eds.). MIT Press (1970) and Jackiw, R.: In: Lectures on current algebra and its applications. Princeton, NJ: Princeton University Press 1972, and references quoted therein
2. See e.g. Stora, R.: Continuum gauge theories. In: New developments in quantum field theories and statistical mechanics. Levy, H., Mitter, P. (eds.). New York: Plenum Press 1977, and references quoted therein
3. For the mathematical set up of this cohomology see Bonoran, L., Cotta-Ramusino, P.: Some remarks on BRS transformations, anomalies, and the cohomology of the Lie algebra of the group of gauge transformations. Commun. Math. Phys.87, 589 (1983)
4. See e.g. Becchi, C., Rouet, A., Stora, R.: In: Renormalization theory, Velo, G., Wightman, A.S. (eds.). Amsterdam: Reidel 1976, and references quoted therein
5. Chern, S.S., Simons, J.: Characteristic forms and geometric invariants. Ann. Math.99, 48 (1974)