1. U. Grenander G. Szegö Toeplitz Forms and their Applications (Chelsea Publ., New York, 1955).
2. Problem 11396;Letac;Amer. Math. Monthly,2008
3. Inequalities concerning polynomials and trigonometric polynomials;Van der Corput;Proc. Kon. Ned. Akad. Wetensch.,1946