2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/202686We present the analytic next-to-next-to-leading perturbative QCD corrections in the leading twist approximation for the moments N=2,4,6,8 of the flavour singlet deep inelastic structure functions F_2 and F_L. We calculate the three-loop anomalous dimensions of the corresponding singlet operators and the three-loop coefficient functions of the structure functions F_L and F_2. In addition, we obtained the 10th moment for the non-singlet structure functions in the same order of perturbative QCD. We perform an analysis of the obtained results.46 pages, the complete Postscript file of this preprint (including 9 figures) is available at ftp://nikhefh.nikhef.nl/pub/preprints/96-010.ps.ZHigh Energy Physics - Phenomenologytext