Piccione, P. A variational theory for light rays in convex subsets of stably causal lorentzian manifolds.

Piccione, Paolo. A Variational Theory for Light Rays in Convex Subsets of Stably Causal Lorentzian Manifolds.

Piccione, Paolo. A Variational Theory for Light Rays in Convex Subsets of Stably Causal Lorentzian Manifolds.