1. G.V. Badalyan, Generalization of Legendre polynomials and some of their applications. Akad, Nauk Armyan SSR Izv. Ser. Fiz-Mat. Estest. Tekhn. Nauk 8, 1–28 (1955)
2. A.S. Besicovitch, Almost Periodic Functions (Dover, New York, 1954)
3. H. Bohr, Almost Periodic Functions (Chelsea, New York, 1947)
4. P. Borwein, T. Erdelyi, Polynomials and Polynomial Inequalities (Springer, New York, 1995)
5. D.K. Dimitrov, W.D. Oliveira, An Extremal Problem Related to Generalizations of the Nyman-Beurling and Baez-Duarte Criteria (manuscript)