Kholshevnikov, Konstantin V., and Vakhit Sh. Shaidulin. “Estimates of Sums of Integrals of Legendre Polynomial”. Vestnik of Saint Petersburg University. Mathematics. Mechanics. Astronomy, vol. 3, no. 2, Oct. 2020, p. 1, doi:10.21638/11701/spbu01.2016.208.