1. Atiyah M.F.: Complex analytic connections in fibre bundles. Trans. Am. Math. Soc. 85, 181207 (1957)
2. Benini, M., Dappiaggi, C., Schenkel, A.: The Maxwell field on curved spacetimes: a principal bundle approach (in preparation)
3. Bär, C., Ginoux, N.: Classical and quantum fields on Lorentzian manifolds. Springer Proc. Math. 17, 359 (2011). arXiv:1104.1158 (math-ph)
4. Bär, C., Ginoux, N., Pfäffle, F.: Wave equations on Lorenzian manifolds and quantization. Zürich, Switzerland: Eur. Math. Soc. (2007). arXiv:0806.1036 (math.DG)
5. Bernal, A.N., Sánchez, M.: Smoothness of time functions and the metric splitting of globally hyperbolic space-times. Commun. Math. Phys. 257, 43 (2005) (gr-qc/0401112)