1.1: International Terrestrial Reference Frame: strengths, weaknesses and strategies for future improvements

Number： 7   

1.2: Advancements and open problems in global reference frame theory and methodology

Number： 6   

1.3: Terrestrial and space geodetic ties for multi-technique combinations

Number： 10   

1.4: Regional reference frames and networks

Number： 9   

1.5: Comparison and combination of space geodesy techniques for improving consistency between TRF, CRF and EOPs

Number： 5   

1.6: Vertical Reference Systems: methodologies, realization, and new technologies

Number： 2