We study the interlacing properties of zeros of para–orthogonal polynomials
associated with a nontrivial probability measure supported on the unit circle dμ
and para–orthogonal polynomials associated with a modification of dμ by the addition
of a pure mass point, also called Uvarov transformation. Moreover, as a direct
consequence of our approach, we present some results related with the Christoffel
transformation.info:eu-repo/semantics/publishedVersio
