Universal R-matrix as integral operator

We derive the integral operator form for the general rational solution of the Yang-Baxter equation with sl(2 vertical bar 1) symmetry. Considering the defining relations for the kernel of the R-operator as a system of second order differential equations we observe remarkable reduction to a system of simple first order equations. The obtained kernel of R-operator has a very simple structure. To illustrate all this in the simplest situation we treat also the sl(2) case