The purpose of thes paper is to show regularity of (0,1,... r-2,r) and (0,1,... r-2,r)* interpolations on the sets obtained by projecting vertically the zeros of
\((1-x^2)P_n^{(\alpha , \beta)} \ \ \ \ \ \ (-1<\alpha , \beta <= \frac {1}{2})\\ (1-x)P_n^{(\alpha , \beta)} \ \ \ \ \ \ (-1<\alpha<= \frac {1}{2} ,-1< \beta <= \frac {1}{2})\)
and
\((1+x)P_n^{(\alpha , \beta)} \ \ \ \ \ \ (-1<\alpha<=\frac {1}{2} , -1 <\beta <= \frac {1}{2})\\ \)
respectively onto the unit circle, where \(P_n^{ ({\alpha , \beta})}(x)\) stand for the
th Jacobi polynomial.