Given two functions and Analytic in with a simple loop Homotopic to a point in , if for all on , then and have the same number of Roots inside .

**References**

Szegö, G. *Orthogonal Polynomials, 4th ed.* Providence, RI:
Amer. Math. Soc., p. 22, 1975.

© 1996-9

1999-05-25