GANELIUS, Tord. On one-sided approximation by trigonometrical polynomials. MATHEMATICA SCANDINAVICA, [S. l.], v. 4, p. 247–258, 1956. DOI: 10.7146/math.scand.a-10473. Disponível em: https://tidsskrift.dk/math/article/view/10473. Acesso em: 14 aug. 2026.