Isoperimetric inequalities for Riemannian products (Q1080192)

Let M be a smooth Riemannian manifold. We say that the f-isoperimetric inequality holds on M if for any open subset \(D\subset M\) of finite volume v with a smooth boundary the measure of codimension 1 of \(\partial D\) is not less than f(v). In the present paper the author finds an isoperimetric inequality for the product \(M_ 1\times M_ 2\) if isoperimetric inequalities on the manifolds \(M_ 1\) and \(M_ 2\) are known.