There are many models developed for the adjustment of the 2D or 2D+1D geodetic networks, both on the ellipsoid surface and in
the map projection plane. These models are widely used by practitioners. In this paper we presented two new mathematical
models for the adjustment of combined geodetic measurements and networks (those collected using Global Navigation Satellite
System (GNSS) technology plus earlier terrestrial methods). Such combined networks can be adjusted either in a Cartesian
geocentric or in an ellipsoidal local coordinate system, both which are appropriate 3D coordinate systems. A MATLAB code was
developed for the implementation of these models.