7775 20260108165427.0 10.1007/s10291-025-01847-3 DOI SCART-2026-0044 Guo, Jiang Continuous time and frequency transfer achieved by multi-day GPS/Galileo/BDS integer precise point positioning 2025 NO Defraigne, Pascale Pinat, Elisa Gps Solutions 29 2025 3 pascale.defraigne@ksb-orb.be published in REFERD