1. E. Abbena, A. Gray and L. Vanhecke: Steiner's formula for the volumes of parallel hypersurfaces in a Riemannian manifold. Ann. Scuola Norm. Sup. Pisa Cl. Sci. (to appear).
2. The Euler number of a Riemannian manifold;Allendoerfer;Am. J. Math.,1940
3. Steiner's formula on a general Sn+1;Allendoerfer;Bull. Am. Math. Soc.,1948
4. Global differential geometry of imbedded manifold;Allendoerfer,1958
5. The Gauss–Bonnet theorem for Riemannian polyhedra;Allendoerfer;Trans. Am. Math. Soc.,1943