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Zajdel, R., Masoumi, S., Sośnica, K., Gałdyn, F., Strugarek D., Bury G. Combination and SLR validation of IGS Repro3 orbits for ITRF2020. J Geod, Vol. 97 No. 87 (2023), pp. 1-29. https://doi.org/10.1007/s00190-023-01777-3 (Algorithm of GPS, GLONASS, and Galileo orbit combination as the official IGS Repro3 product in ITRF2020. The orbits are evaluated using the comparisons to the combined orbits, as well as using SLR data to Galileo and GLONASS.)