Un lemme de prolongement holomorphe et ses applications

We prove that an holomorphic function defined in the neighborhood of an algebraic knot f⁻¹(0)∩S(0,ε) in dimension ?3, can be extended along the hypersurface f⁻¹(0)∩B(0,ε). As an application we give a new proof of the Malgrange's singular Frobenius theorem.