1. Geometry of spaces of constant curvature;Alekseevskij,1993
2. The Hadamard–Cartan theorem in locally convex metric spaces;Alexander;Enseign. Math.,1990
3. Comparison theorems for curves of bounded geodesic curvature in metric spaces of curvature bounded above;Alexander;Differential Geom. Appl.,1996
4. The Fary–Milnor theorem in Hadamard manifolds;Alexander;Proc. Amer. Math. Soc.,1998
5. A.D. Alexandrov, Theory of curves based on the approximation by polygonal lines, Nautch. Sess. Leningr. Univer., Tesisy Dokl. na Sektch. Matem. Nauk., 1946