Based on the analysis, points from double leveling network and from GNSS stations (ASG
EUPOS) network that are within the distance not exceeding 10 km, can be considered as corresponding to the same nodal point (pseudo-nodal point).
In 2008 Polish Head Office of Geodesy and Cartography established a GBAS called ASG-EUPOS as a part of
EUPOS Project (www.eupos.org).
This resulted from a gradual launch of the particular ASG
EUPOS stations, as well as from initial selection of the data.
and Kaminski, P.: 2010, Investigation on stability of mountainous
EUPOS stations' coordinates, Acta Geodyn.