HYLTÉN-CAVALLIUS, Carl. Some extremal problems for trigonometrical and complex polynomials. Mathematica Scandinavica, Berkeley, CA, United States, v. 3, p. 5–20, 1955. DOI: 10.7146/math.scand.a-10420. Disponível em: https://journals.msp.org/mscand/article/view/2900. Acesso em: 8 sep. 2026.