Key points are not available for this paper at this time.
Dual angles in affine space.104 3. Dual angles in Euclidean space.109 4. Convex cells and their tubes.110 5. Curved cells and their tubes.112 6. Gauss-Bonnet formula for imbedded cells.116 7. Gauss-Bonnet formula for Riemannian polyhedra.
Allendoerfer et al. (1943) studied this question.