On the computation of zeros and turning points of Bessel functions R. Piessens — 1990 Δελτίο της Ελληνικής Μαθηματικής Εταιρίας
Construction of Cubature Formulas of Degree Eleven for Symmetric Planar Regions "Using" Orthogonal Polynomials. A. Haegemanns; R. Piessens Numerische Mathematik