A simple proof of curvature estimate for convex solution of

Guan-Ren-Wang [Comm. Pure Appl. Math. 68 (2015), pp. 1287–1325] established the curvature estimate of convex hypersurface satisfying Weingarten equation σ k ( κ<!-- κ <mml:mi>X stretchy="false">) = f , ν<!-- ν <mml:annotation encoding="application/x-tex">\sigma _{k}(\kappa (X)) = f(X,\nu (X)) . In this note, we give a simple proof result.