Proximal smoothness and the lower- C 2 property. Clarke, F.H.; Stern, R.J.; Wolenski, P.R. — 1995 Journal of Convex Analysis
Complements, approximations, smoothings and invariance properties. Clarke, F.H.; Ledyaev, Yu.S.; Stern, R.J. — 1997 Journal of Convex Analysis
The Relationship between Homology and Topological Manifolds via Homology Transversaltiy D.E. Galewski; R.J. Stern — 1977 Inventiones mathematicae