Stokes type theorem for tensors (Q919627)

Let u be a vector field, A a tensor field of type (2,0) in Euclidean three-space. The tensor product \(u\otimes A\) can be considered as a differential form whose values are (2,0)-tensors. The author integrates \(u\otimes A\) over the boundary of a regular surface element using the Stokes' theorem and the product rule for the exterior differentiation of the integrand. Further specializations are made.